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-rw-r--r--tccelf.c3504
1 files changed, 3504 insertions, 0 deletions
diff --git a/tccelf.c b/tccelf.c
new file mode 100644
index 0000000..1f87946
--- /dev/null
+++ b/tccelf.c
@@ -0,0 +1,3504 @@
+/*
+ * ELF file handling for TCC
+ *
+ * Copyright (c) 2001-2004 Fabrice Bellard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "tcc.h"
+
+/* Define this to get some debug output during relocation processing. */
+#undef DEBUG_RELOC
+
+/* XXX: avoid static variable */
+static int new_undef_sym = 0; /* Is there a new undefined sym since last new_undef_sym() */
+
+ST_FUNC int put_elf_str(Section *s, const char *sym)
+{
+ int offset, len;
+ char *ptr;
+
+ len = strlen(sym) + 1;
+ offset = s->data_offset;
+ ptr = section_ptr_add(s, len);
+ memcpy(ptr, sym, len);
+ return offset;
+}
+
+/* elf symbol hashing function */
+static unsigned long elf_hash(const unsigned char *name)
+{
+ unsigned long h = 0, g;
+
+ while (*name) {
+ h = (h << 4) + *name++;
+ g = h & 0xf0000000;
+ if (g)
+ h ^= g >> 24;
+ h &= ~g;
+ }
+ return h;
+}
+
+/* rebuild hash table of section s */
+/* NOTE: we do factorize the hash table code to go faster */
+static void rebuild_hash(Section *s, unsigned int nb_buckets)
+{
+ ElfW(Sym) *sym;
+ int *ptr, *hash, nb_syms, sym_index, h;
+ unsigned char *strtab;
+
+ strtab = s->link->data;
+ nb_syms = s->data_offset / sizeof(ElfW(Sym));
+
+ s->hash->data_offset = 0;
+ ptr = section_ptr_add(s->hash, (2 + nb_buckets + nb_syms) * sizeof(int));
+ ptr[0] = nb_buckets;
+ ptr[1] = nb_syms;
+ ptr += 2;
+ hash = ptr;
+ memset(hash, 0, (nb_buckets + 1) * sizeof(int));
+ ptr += nb_buckets + 1;
+
+ sym = (ElfW(Sym) *)s->data + 1;
+ for(sym_index = 1; sym_index < nb_syms; sym_index++) {
+ if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
+ h = elf_hash(strtab + sym->st_name) % nb_buckets;
+ *ptr = hash[h];
+ hash[h] = sym_index;
+ } else {
+ *ptr = 0;
+ }
+ ptr++;
+ sym++;
+ }
+}
+
+/* return the symbol number */
+ST_FUNC int put_elf_sym(Section *s, addr_t value, unsigned long size,
+ int info, int other, int shndx, const char *name)
+{
+ int name_offset, sym_index;
+ int nbuckets, h;
+ ElfW(Sym) *sym;
+ Section *hs;
+
+ sym = section_ptr_add(s, sizeof(ElfW(Sym)));
+ if (name)
+ name_offset = put_elf_str(s->link, name);
+ else
+ name_offset = 0;
+ /* XXX: endianness */
+ sym->st_name = name_offset;
+ sym->st_value = value;
+ sym->st_size = size;
+ sym->st_info = info;
+ sym->st_other = other;
+ sym->st_shndx = shndx;
+ sym_index = sym - (ElfW(Sym) *)s->data;
+ hs = s->hash;
+ if (hs) {
+ int *ptr, *base;
+ ptr = section_ptr_add(hs, sizeof(int));
+ base = (int *)hs->data;
+ /* only add global or weak symbols */
+ if (ELFW(ST_BIND)(info) != STB_LOCAL) {
+ /* add another hashing entry */
+ nbuckets = base[0];
+ h = elf_hash((unsigned char *) name) % nbuckets;
+ *ptr = base[2 + h];
+ base[2 + h] = sym_index;
+ base[1]++;
+ /* we resize the hash table */
+ hs->nb_hashed_syms++;
+ if (hs->nb_hashed_syms > 2 * nbuckets) {
+ rebuild_hash(s, 2 * nbuckets);
+ }
+ } else {
+ *ptr = 0;
+ base[1]++;
+ }
+ }
+ return sym_index;
+}
+
+/* find global ELF symbol 'name' and return its index. Return 0 if not
+ found. */
+ST_FUNC int find_elf_sym(Section *s, const char *name)
+{
+ ElfW(Sym) *sym;
+ Section *hs;
+ int nbuckets, sym_index, h;
+ const char *name1;
+
+ hs = s->hash;
+ if (!hs)
+ return 0;
+ nbuckets = ((int *)hs->data)[0];
+ h = elf_hash((unsigned char *) name) % nbuckets;
+ sym_index = ((int *)hs->data)[2 + h];
+ while (sym_index != 0) {
+ sym = &((ElfW(Sym) *)s->data)[sym_index];
+ name1 = (char *) s->link->data + sym->st_name;
+ if (!strcmp(name, name1))
+ return sym_index;
+ sym_index = ((int *)hs->data)[2 + nbuckets + sym_index];
+ }
+ return 0;
+}
+
+/* return elf symbol value, signal error if 'err' is nonzero */
+ST_FUNC addr_t get_elf_sym_addr(TCCState *s, const char *name, int err)
+{
+ int sym_index;
+ ElfW(Sym) *sym;
+
+ sym_index = find_elf_sym(s->symtab, name);
+ sym = &((ElfW(Sym) *)s->symtab->data)[sym_index];
+ if (!sym_index || sym->st_shndx == SHN_UNDEF) {
+ if (err)
+ tcc_error("%s not defined", name);
+ return 0;
+ }
+ return sym->st_value;
+}
+
+/* return elf symbol value */
+LIBTCCAPI void *tcc_get_symbol(TCCState *s, const char *name)
+{
+ return (void*)(uintptr_t)get_elf_sym_addr(s, name, 0);
+}
+
+#if defined TCC_IS_NATIVE || defined TCC_TARGET_PE
+/* return elf symbol value or error */
+ST_FUNC void* tcc_get_symbol_err(TCCState *s, const char *name)
+{
+ return (void*)(uintptr_t)get_elf_sym_addr(s, name, 1);
+}
+#endif
+
+/* add an elf symbol : check if it is already defined and patch
+ it. Return symbol index. NOTE that sh_num can be SHN_UNDEF. */
+ST_FUNC int add_elf_sym(Section *s, addr_t value, unsigned long size,
+ int info, int other, int sh_num, const char *name)
+{
+ ElfW(Sym) *esym;
+ int sym_bind, sym_index, sym_type, esym_bind;
+ unsigned char sym_vis, esym_vis, new_vis;
+
+ sym_bind = ELFW(ST_BIND)(info);
+ sym_type = ELFW(ST_TYPE)(info);
+ sym_vis = ELFW(ST_VISIBILITY)(other);
+
+ if (sym_bind != STB_LOCAL) {
+ /* we search global or weak symbols */
+ sym_index = find_elf_sym(s, name);
+ if (!sym_index)
+ goto do_def;
+ esym = &((ElfW(Sym) *)s->data)[sym_index];
+ if (esym->st_shndx != SHN_UNDEF) {
+ esym_bind = ELFW(ST_BIND)(esym->st_info);
+ /* propagate the most constraining visibility */
+ /* STV_DEFAULT(0)<STV_PROTECTED(3)<STV_HIDDEN(2)<STV_INTERNAL(1) */
+ esym_vis = ELFW(ST_VISIBILITY)(esym->st_other);
+ if (esym_vis == STV_DEFAULT) {
+ new_vis = sym_vis;
+ } else if (sym_vis == STV_DEFAULT) {
+ new_vis = esym_vis;
+ } else {
+ new_vis = (esym_vis < sym_vis) ? esym_vis : sym_vis;
+ }
+ esym->st_other = (esym->st_other & ~ELFW(ST_VISIBILITY)(-1))
+ | new_vis;
+ other = esym->st_other; /* in case we have to patch esym */
+ if (sh_num == SHN_UNDEF) {
+ /* ignore adding of undefined symbol if the
+ corresponding symbol is already defined */
+ } else if (sym_bind == STB_GLOBAL && esym_bind == STB_WEAK) {
+ /* global overrides weak, so patch */
+ goto do_patch;
+ } else if (sym_bind == STB_WEAK && esym_bind == STB_GLOBAL) {
+ /* weak is ignored if already global */
+ } else if (sym_bind == STB_WEAK && esym_bind == STB_WEAK) {
+ /* keep first-found weak definition, ignore subsequents */
+ } else if (sym_vis == STV_HIDDEN || sym_vis == STV_INTERNAL) {
+ /* ignore hidden symbols after */
+ } else if (esym->st_shndx == SHN_COMMON
+ && (sh_num < SHN_LORESERVE || sh_num == SHN_COMMON)) {
+ /* gr: Happens with 'tcc ... -static tcctest.c' on e.g. Ubuntu 6.01
+ No idea if this is the correct solution ... */
+ goto do_patch;
+ } else if (s == tcc_state->dynsymtab_section) {
+ /* we accept that two DLL define the same symbol */
+ } else {
+#if 0
+ printf("new_bind=%x new_shndx=%x new_vis=%x old_bind=%x old_shndx=%x old_vis=%x\n",
+ sym_bind, sh_num, new_vis, esym_bind, esym->st_shndx, esym_vis);
+#endif
+ tcc_error_noabort("'%s' defined twice", name);
+ }
+ } else {
+ do_patch:
+ esym->st_info = ELFW(ST_INFO)(sym_bind, sym_type);
+ esym->st_shndx = sh_num;
+ new_undef_sym = 1;
+ esym->st_value = value;
+ esym->st_size = size;
+ esym->st_other = other;
+ }
+ } else {
+ do_def:
+ sym_index = put_elf_sym(s, value, size,
+ ELFW(ST_INFO)(sym_bind, sym_type), other,
+ sh_num, name);
+ }
+ return sym_index;
+}
+
+/* put relocation */
+ST_FUNC void put_elf_reloca(Section *symtab, Section *s, unsigned long offset,
+ int type, int symbol, addr_t addend)
+{
+ char buf[256];
+ Section *sr;
+ ElfW_Rel *rel;
+
+ sr = s->reloc;
+ if (!sr) {
+ /* if no relocation section, create it */
+ snprintf(buf, sizeof(buf), REL_SECTION_FMT, s->name);
+ /* if the symtab is allocated, then we consider the relocation
+ are also */
+ sr = new_section(tcc_state, buf, SHT_RELX, symtab->sh_flags);
+ sr->sh_entsize = sizeof(ElfW_Rel);
+ sr->link = symtab;
+ sr->sh_info = s->sh_num;
+ s->reloc = sr;
+ }
+ rel = section_ptr_add(sr, sizeof(ElfW_Rel));
+ rel->r_offset = offset;
+ rel->r_info = ELFW(R_INFO)(symbol, type);
+#if defined(TCC_TARGET_ARM64) || defined(TCC_TARGET_X86_64)
+ rel->r_addend = addend;
+#else
+ if (addend)
+ tcc_error("non-zero addend on REL architecture");
+#endif
+}
+
+ST_FUNC void put_elf_reloc(Section *symtab, Section *s, unsigned long offset,
+ int type, int symbol)
+{
+ put_elf_reloca(symtab, s, offset, type, symbol, 0);
+}
+
+/* put stab debug information */
+
+ST_FUNC void put_stabs(const char *str, int type, int other, int desc,
+ unsigned long value)
+{
+ Stab_Sym *sym;
+
+ sym = section_ptr_add(stab_section, sizeof(Stab_Sym));
+ if (str) {
+ sym->n_strx = put_elf_str(stabstr_section, str);
+ } else {
+ sym->n_strx = 0;
+ }
+ sym->n_type = type;
+ sym->n_other = other;
+ sym->n_desc = desc;
+ sym->n_value = value;
+}
+
+ST_FUNC void put_stabs_r(const char *str, int type, int other, int desc,
+ unsigned long value, Section *sec, int sym_index)
+{
+ put_stabs(str, type, other, desc, value);
+ put_elf_reloc(symtab_section, stab_section,
+ stab_section->data_offset - sizeof(unsigned int),
+ R_DATA_32, sym_index);
+}
+
+ST_FUNC void put_stabn(int type, int other, int desc, int value)
+{
+ put_stabs(NULL, type, other, desc, value);
+}
+
+ST_FUNC void put_stabd(int type, int other, int desc)
+{
+ put_stabs(NULL, type, other, desc, 0);
+}
+
+/* Browse each elem of type <type> in section <sec> starting at elem <startoff>
+ using variable <elem> */
+#define for_each_elem(sec, startoff, elem, type) \
+ for (elem = (type *) sec->data + startoff; \
+ elem < (type *) (sec->data + sec->data_offset); elem++)
+
+/* In an ELF file symbol table, the local symbols must appear below
+ the global and weak ones. Since TCC cannot sort it while generating
+ the code, we must do it after. All the relocation tables are also
+ modified to take into account the symbol table sorting */
+static void sort_syms(TCCState *s1, Section *s)
+{
+ int *old_to_new_syms;
+ ElfW(Sym) *new_syms;
+ int nb_syms, i;
+ ElfW(Sym) *p, *q;
+ ElfW_Rel *rel;
+ Section *sr;
+ int type, sym_index;
+
+ nb_syms = s->data_offset / sizeof(ElfW(Sym));
+ new_syms = tcc_malloc(nb_syms * sizeof(ElfW(Sym)));
+ old_to_new_syms = tcc_malloc(nb_syms * sizeof(int));
+
+ /* first pass for local symbols */
+ p = (ElfW(Sym) *)s->data;
+ q = new_syms;
+ for(i = 0; i < nb_syms; i++) {
+ if (ELFW(ST_BIND)(p->st_info) == STB_LOCAL) {
+ old_to_new_syms[i] = q - new_syms;
+ *q++ = *p;
+ }
+ p++;
+ }
+ /* save the number of local symbols in section header */
+ s->sh_info = q - new_syms;
+
+ /* then second pass for non local symbols */
+ p = (ElfW(Sym) *)s->data;
+ for(i = 0; i < nb_syms; i++) {
+ if (ELFW(ST_BIND)(p->st_info) != STB_LOCAL) {
+ old_to_new_syms[i] = q - new_syms;
+ *q++ = *p;
+ }
+ p++;
+ }
+
+ /* we copy the new symbols to the old */
+ memcpy(s->data, new_syms, nb_syms * sizeof(ElfW(Sym)));
+ tcc_free(new_syms);
+
+ /* now we modify all the relocations */
+ for(i = 1; i < s1->nb_sections; i++) {
+ sr = s1->sections[i];
+ if (sr->sh_type == SHT_RELX && sr->link == s) {
+ for_each_elem(sr, 0, rel, ElfW_Rel) {
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ type = ELFW(R_TYPE)(rel->r_info);
+ sym_index = old_to_new_syms[sym_index];
+ rel->r_info = ELFW(R_INFO)(sym_index, type);
+ }
+ }
+ }
+
+ tcc_free(old_to_new_syms);
+}
+
+/* relocate common symbols in the .bss section */
+ST_FUNC void relocate_common_syms(void)
+{
+ ElfW(Sym) *sym;
+ unsigned long offset, align;
+
+ for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
+ if (sym->st_shndx == SHN_COMMON) {
+ /* align symbol */
+ align = sym->st_value;
+ offset = bss_section->data_offset;
+ offset = (offset + align - 1) & -align;
+ sym->st_value = offset;
+ sym->st_shndx = bss_section->sh_num;
+ offset += sym->st_size;
+ bss_section->data_offset = offset;
+ }
+ }
+}
+
+/* relocate symbol table, resolve undefined symbols if do_resolve is
+ true and output error if undefined symbol. */
+ST_FUNC void relocate_syms(TCCState *s1, int do_resolve)
+{
+ ElfW(Sym) *sym, *esym;
+ int sym_bind, sh_num, sym_index;
+ const char *name;
+
+ for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
+ sh_num = sym->st_shndx;
+ if (sh_num == SHN_UNDEF) {
+ name = (char *) strtab_section->data + sym->st_name;
+ /* Use ld.so to resolve symbol for us (for tcc -run) */
+ if (do_resolve) {
+#if defined TCC_IS_NATIVE && !defined _WIN32
+ void *addr;
+ name = (char *) symtab_section->link->data + sym->st_name;
+ addr = resolve_sym(s1, name);
+ if (addr) {
+ sym->st_value = (addr_t)addr;
+#ifdef DEBUG_RELOC
+ printf ("relocate_sym: %s -> 0x%lx\n", name, sym->st_value);
+#endif
+ goto found;
+ }
+#endif
+ } else if (s1->dynsym) {
+ /* if dynamic symbol exist, then use it */
+ sym_index = find_elf_sym(s1->dynsym, name);
+ if (sym_index) {
+ esym = &((ElfW(Sym) *)s1->dynsym->data)[sym_index];
+ sym->st_value = esym->st_value;
+ goto found;
+ }
+ }
+ /* XXX: _fp_hw seems to be part of the ABI, so we ignore
+ it */
+ if (!strcmp(name, "_fp_hw"))
+ goto found;
+ /* only weak symbols are accepted to be undefined. Their
+ value is zero */
+ sym_bind = ELFW(ST_BIND)(sym->st_info);
+ if (sym_bind == STB_WEAK) {
+ sym->st_value = 0;
+ } else {
+ tcc_error_noabort("undefined symbol '%s'", name);
+ }
+ } else if (sh_num < SHN_LORESERVE) {
+ /* add section base */
+ sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
+ }
+ found: ;
+ }
+}
+
+/* relocate a given section (CPU dependent) by applying the relocations
+ in the associated relocation section */
+ST_FUNC void relocate_section(TCCState *s1, Section *s)
+{
+ Section *sr = s->reloc;
+ ElfW_Rel *rel;
+ ElfW(Sym) *sym;
+ int type, sym_index;
+ unsigned char *ptr;
+ addr_t val, addr;
+#if defined TCC_TARGET_I386 || defined TCC_TARGET_X86_64
+ ElfW_Rel *qrel = (ElfW_Rel *) sr->data; /* ptr to next reloc entry reused */
+ int esym_index;
+#endif
+
+ for_each_elem(sr, 0, rel, ElfW_Rel) {
+ ptr = s->data + rel->r_offset;
+
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ val = sym->st_value;
+#if defined(TCC_TARGET_ARM64) || defined(TCC_TARGET_X86_64)
+ val += rel->r_addend;
+#endif
+ type = ELFW(R_TYPE)(rel->r_info);
+ addr = s->sh_addr + rel->r_offset;
+
+ /* CPU specific */
+ switch(type) {
+#if defined(TCC_TARGET_I386)
+ case R_386_32:
+ if (s1->output_type == TCC_OUTPUT_DLL) {
+ esym_index = s1->symtab_to_dynsym[sym_index];
+ qrel->r_offset = rel->r_offset;
+ if (esym_index) {
+ qrel->r_info = ELFW(R_INFO)(esym_index, R_386_32);
+ qrel++;
+ break;
+ } else {
+ qrel->r_info = ELFW(R_INFO)(0, R_386_RELATIVE);
+ qrel++;
+ }
+ }
+ *(int *)ptr += val;
+ break;
+ case R_386_PC32:
+ if (s1->output_type == TCC_OUTPUT_DLL) {
+ /* DLL relocation */
+ esym_index = s1->symtab_to_dynsym[sym_index];
+ if (esym_index) {
+ qrel->r_offset = rel->r_offset;
+ qrel->r_info = ELFW(R_INFO)(esym_index, R_386_PC32);
+ qrel++;
+ break;
+ }
+ }
+ *(int *)ptr += val - addr;
+ break;
+ case R_386_PLT32:
+ *(int *)ptr += val - addr;
+ break;
+ case R_386_GLOB_DAT:
+ case R_386_JMP_SLOT:
+ *(int *)ptr = val;
+ break;
+ case R_386_GOTPC:
+ *(int *)ptr += s1->got->sh_addr - addr;
+ break;
+ case R_386_GOTOFF:
+ *(int *)ptr += val - s1->got->sh_addr;
+ break;
+ case R_386_GOT32:
+ /* we load the got offset */
+ *(int *)ptr += s1->sym_attrs[sym_index].got_offset;
+ break;
+ case R_386_16:
+ if (s1->output_format != TCC_OUTPUT_FORMAT_BINARY) {
+ output_file:
+ tcc_error("can only produce 16-bit binary files");
+ }
+ *(short *)ptr += val;
+ break;
+ case R_386_PC16:
+ if (s1->output_format != TCC_OUTPUT_FORMAT_BINARY)
+ goto output_file;
+ *(short *)ptr += val - addr;
+ break;
+#elif defined(TCC_TARGET_ARM)
+ case R_ARM_PC24:
+ case R_ARM_CALL:
+ case R_ARM_JUMP24:
+ case R_ARM_PLT32:
+ {
+ int x, is_thumb, is_call, h, blx_avail, is_bl, th_ko;
+ x = (*(int *) ptr) & 0xffffff;
+ if (sym->st_shndx == SHN_UNDEF)
+ val = s1->plt->sh_addr;
+#ifdef DEBUG_RELOC
+ printf ("reloc %d: x=0x%x val=0x%x ", type, x, val);
+#endif
+ (*(int *)ptr) &= 0xff000000;
+ if (x & 0x800000)
+ x -= 0x1000000;
+ x <<= 2;
+ blx_avail = (TCC_ARM_VERSION >= 5);
+ is_thumb = val & 1;
+ is_bl = (*(unsigned *) ptr) >> 24 == 0xeb;
+ is_call = (type == R_ARM_CALL || (type == R_ARM_PC24 && is_bl));
+ x += val - addr;
+#ifdef DEBUG_RELOC
+ printf (" newx=0x%x name=%s\n", x,
+ (char *) symtab_section->link->data + sym->st_name);
+#endif
+ h = x & 2;
+ th_ko = (x & 3) && (!blx_avail || !is_call);
+ if (th_ko || x >= 0x2000000 || x < -0x2000000)
+ tcc_error("can't relocate value at %x,%d",addr, type);
+ x >>= 2;
+ x &= 0xffffff;
+ /* Only reached if blx is avail and it is a call */
+ if (is_thumb) {
+ x |= h << 24;
+ (*(int *)ptr) = 0xfa << 24; /* bl -> blx */
+ }
+ (*(int *) ptr) |= x;
+ }
+ break;
+ /* Since these relocations only concern Thumb-2 and blx instruction was
+ introduced before Thumb-2, we can assume blx is available and not
+ guard its use */
+ case R_ARM_THM_PC22:
+ case R_ARM_THM_JUMP24:
+ {
+ int x, hi, lo, s, j1, j2, i1, i2, imm10, imm11;
+ int to_thumb, is_call, to_plt, blx_bit = 1 << 12;
+ Section *plt;
+
+ /* weak reference */
+ if (sym->st_shndx == SHN_UNDEF &&
+ ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
+ break;
+
+ /* Get initial offset */
+ hi = (*(uint16_t *)ptr);
+ lo = (*(uint16_t *)(ptr+2));
+ s = (hi >> 10) & 1;
+ j1 = (lo >> 13) & 1;
+ j2 = (lo >> 11) & 1;
+ i1 = (j1 ^ s) ^ 1;
+ i2 = (j2 ^ s) ^ 1;
+ imm10 = hi & 0x3ff;
+ imm11 = lo & 0x7ff;
+ x = (s << 24) | (i1 << 23) | (i2 << 22) |
+ (imm10 << 12) | (imm11 << 1);
+ if (x & 0x01000000)
+ x -= 0x02000000;
+
+ /* Relocation infos */
+ to_thumb = val & 1;
+ plt = s1->plt;
+ to_plt = (val >= plt->sh_addr) &&
+ (val < plt->sh_addr + plt->data_offset);
+ is_call = (type == R_ARM_THM_PC22);
+
+ /* Compute final offset */
+ if (to_plt && !is_call) /* Point to 1st instr of Thumb stub */
+ x -= 4;
+ x += val - addr;
+ if (!to_thumb && is_call) {
+ blx_bit = 0; /* bl -> blx */
+ x = (x + 3) & -4; /* Compute offset from aligned PC */
+ }
+
+ /* Check that relocation is possible
+ * offset must not be out of range
+ * if target is to be entered in arm mode:
+ - bit 1 must not set
+ - instruction must be a call (bl) or a jump to PLT */
+ if (!to_thumb || x >= 0x1000000 || x < -0x1000000)
+ if (to_thumb || (val & 2) || (!is_call && !to_plt))
+ tcc_error("can't relocate value at %x,%d",addr, type);
+
+ /* Compute and store final offset */
+ s = (x >> 24) & 1;
+ i1 = (x >> 23) & 1;
+ i2 = (x >> 22) & 1;
+ j1 = s ^ (i1 ^ 1);
+ j2 = s ^ (i2 ^ 1);
+ imm10 = (x >> 12) & 0x3ff;
+ imm11 = (x >> 1) & 0x7ff;
+ (*(uint16_t *)ptr) = (uint16_t) ((hi & 0xf800) |
+ (s << 10) | imm10);
+ (*(uint16_t *)(ptr+2)) = (uint16_t) ((lo & 0xc000) |
+ (j1 << 13) | blx_bit | (j2 << 11) |
+ imm11);
+ }
+ break;
+ case R_ARM_MOVT_ABS:
+ case R_ARM_MOVW_ABS_NC:
+ {
+ int x, imm4, imm12;
+ if (type == R_ARM_MOVT_ABS)
+ val >>= 16;
+ imm12 = val & 0xfff;
+ imm4 = (val >> 12) & 0xf;
+ x = (imm4 << 16) | imm12;
+ if (type == R_ARM_THM_MOVT_ABS)
+ *(int *)ptr |= x;
+ else
+ *(int *)ptr += x;
+ }
+ break;
+ case R_ARM_THM_MOVT_ABS:
+ case R_ARM_THM_MOVW_ABS_NC:
+ {
+ int x, i, imm4, imm3, imm8;
+ if (type == R_ARM_THM_MOVT_ABS)
+ val >>= 16;
+ imm8 = val & 0xff;
+ imm3 = (val >> 8) & 0x7;
+ i = (val >> 11) & 1;
+ imm4 = (val >> 12) & 0xf;
+ x = (imm3 << 28) | (imm8 << 16) | (i << 10) | imm4;
+ if (type == R_ARM_THM_MOVT_ABS)
+ *(int *)ptr |= x;
+ else
+ *(int *)ptr += x;
+ }
+ break;
+ case R_ARM_PREL31:
+ {
+ int x;
+ x = (*(int *)ptr) & 0x7fffffff;
+ (*(int *)ptr) &= 0x80000000;
+ x = (x * 2) / 2;
+ x += val - addr;
+ if((x^(x>>1))&0x40000000)
+ tcc_error("can't relocate value at %x,%d",addr, type);
+ (*(int *)ptr) |= x & 0x7fffffff;
+ }
+ case R_ARM_ABS32:
+ *(int *)ptr += val;
+ break;
+ case R_ARM_REL32:
+ *(int *)ptr += val - addr;
+ break;
+ case R_ARM_GOTPC:
+ *(int *)ptr += s1->got->sh_addr - addr;
+ break;
+ case R_ARM_GOTOFF:
+ *(int *)ptr += val - s1->got->sh_addr;
+ break;
+ case R_ARM_GOT32:
+ /* we load the got offset */
+ *(int *)ptr += s1->sym_attrs[sym_index].got_offset;
+ break;
+ case R_ARM_COPY:
+ break;
+ case R_ARM_V4BX:
+ /* trade Thumb support for ARMv4 support */
+ if ((0x0ffffff0 & *(int*)ptr) == 0x012FFF10)
+ *(int*)ptr ^= 0xE12FFF10 ^ 0xE1A0F000; /* BX Rm -> MOV PC, Rm */
+ break;
+ case R_ARM_GLOB_DAT:
+ case R_ARM_JUMP_SLOT:
+ *(addr_t *)ptr = val;
+ break;
+ case R_ARM_NONE:
+ /* Nothing to do. Normally used to indicate a dependency
+ on a certain symbol (like for exception handling under EABI). */
+ break;
+ default:
+ fprintf(stderr,"FIXME: handle reloc type %x at %x [%p] to %x\n",
+ type, (unsigned)addr, ptr, (unsigned)val);
+ break;
+#elif defined(TCC_TARGET_ARM64)
+ case R_AARCH64_ABS64:
+ *(uint64_t *)ptr = val;
+ break;
+ case R_AARCH64_ABS32:
+ *(uint32_t *)ptr = val;
+ break;
+ case R_AARCH64_MOVW_UABS_G0_NC:
+ *(uint32_t *)ptr = (*(uint32_t *)ptr & 0xffe0001f) |
+ (val & 0xffff) << 5;
+ break;
+ case R_AARCH64_MOVW_UABS_G1_NC:
+ *(uint32_t *)ptr = (*(uint32_t *)ptr & 0xffe0001f) |
+ (val >> 16 & 0xffff) << 5;
+ break;
+ case R_AARCH64_MOVW_UABS_G2_NC:
+ *(uint32_t *)ptr = (*(uint32_t *)ptr & 0xffe0001f) |
+ (val >> 32 & 0xffff) << 5;
+ break;
+ case R_AARCH64_MOVW_UABS_G3:
+ *(uint32_t *)ptr = (*(uint32_t *)ptr & 0xffe0001f) |
+ (val >> 48 & 0xffff) << 5;
+ break;
+ case R_AARCH64_ADR_PREL_PG_HI21: {
+ uint64_t off = (val >> 12) - (addr >> 12);
+ if ((off + ((uint64_t)1 << 20)) >> 21)
+ tcc_error("R_AARCH64_ADR_PREL_PG_HI21 relocation failed");
+ *(uint32_t *)ptr = (*(uint32_t *)ptr & 0x9f00001f) |
+ (off & 0x1ffffc) << 3 | (off & 3) << 29;
+ break;
+ }
+ case R_AARCH64_ADD_ABS_LO12_NC:
+ *(uint32_t *)ptr = (*(uint32_t *)ptr & 0xffc003ff) |
+ (val & 0xfff) << 10;
+ break;
+ case R_AARCH64_JUMP26:
+ case R_AARCH64_CALL26:
+ /* This check must match the one in build_got_entries, testing
+ if we really need a PLT slot. */
+ if (sym->st_shndx == SHN_UNDEF)
+ /* We've put the PLT slot offset into r_addend when generating
+ it, and that's what we must use as relocation value (adjusted
+ by section offset of course). */
+ val = s1->plt->sh_addr + rel->r_addend;
+#ifdef DEBUG_RELOC
+ printf ("reloc %d @ 0x%lx: val=0x%lx name=%s\n", type, addr, val,
+ (char *) symtab_section->link->data + sym->st_name);
+#endif
+ if (((val - addr) + ((uint64_t)1 << 27)) & ~(uint64_t)0xffffffc)
+ {
+ tcc_error("R_AARCH64_(JUMP|CALL)26 relocation failed (val=%lx, addr=%lx)", addr, val);
+ }
+ *(uint32_t *)ptr = 0x14000000 | (type == R_AARCH64_CALL26) << 31 |
+ ((val - addr) >> 2 & 0x3ffffff);
+ break;
+ case R_AARCH64_ADR_GOT_PAGE: {
+ uint64_t off =
+ (((s1->got->sh_addr +
+ s1->sym_attrs[sym_index].got_offset) >> 12) - (addr >> 12));
+ if ((off + ((uint64_t)1 << 20)) >> 21)
+ tcc_error("R_AARCH64_ADR_GOT_PAGE relocation failed");
+ *(uint32_t *)ptr = (*(uint32_t *)ptr & 0x9f00001f) |
+ (off & 0x1ffffc) << 3 | (off & 3) << 29;
+ break;
+ }
+ case R_AARCH64_LD64_GOT_LO12_NC:
+ *(uint32_t *)ptr = (*(uint32_t *)ptr & 0xfff803ff) |
+ ((s1->got->sh_addr + s1->sym_attrs[sym_index].got_offset)
+ & 0xff8) << 7;
+ break;
+ case R_AARCH64_COPY:
+ break;
+ case R_AARCH64_GLOB_DAT:
+ case R_AARCH64_JUMP_SLOT:
+ /* They don't need addend */
+#ifdef DEBUG_RELOC
+ printf ("reloc %d @ 0x%lx: val=0x%lx name=%s\n", type, addr,
+ val - rel->r_addend,
+ (char *) symtab_section->link->data + sym->st_name);
+#endif
+ *(addr_t *)ptr = val - rel->r_addend;
+ break;
+ default:
+ fprintf(stderr, "FIXME: handle reloc type %x at %x [%p] to %x\n",
+ type, (unsigned)addr, ptr, (unsigned)val);
+ break;
+#elif defined(TCC_TARGET_C67)
+ case R_C60_32:
+ *(int *)ptr += val;
+ break;
+ case R_C60LO16:
+ {
+ uint32_t orig;
+
+ /* put the low 16 bits of the absolute address
+ add to what is already there */
+
+ orig = ((*(int *)(ptr )) >> 7) & 0xffff;
+ orig |= (((*(int *)(ptr+4)) >> 7) & 0xffff) << 16;
+
+ /* patch both at once - assumes always in pairs Low - High */
+
+ *(int *) ptr = (*(int *) ptr & (~(0xffff << 7)) ) | (((val+orig) & 0xffff) << 7);
+ *(int *)(ptr+4) = (*(int *)(ptr+4) & (~(0xffff << 7)) ) | ((((val+orig)>>16) & 0xffff) << 7);
+ }
+ break;
+ case R_C60HI16:
+ break;
+ default:
+ fprintf(stderr,"FIXME: handle reloc type %x at %x [%p] to %x\n",
+ type, (unsigned)addr, ptr, (unsigned)val);
+ break;
+#elif defined(TCC_TARGET_X86_64)
+ case R_X86_64_64:
+ if (s1->output_type == TCC_OUTPUT_DLL) {
+ esym_index = s1->symtab_to_dynsym[sym_index];
+ qrel->r_offset = rel->r_offset;
+ if (esym_index) {
+ qrel->r_info = ELFW(R_INFO)(esym_index, R_X86_64_64);
+ qrel->r_addend = rel->r_addend;
+ qrel++;
+ break;
+ } else {
+ qrel->r_info = ELFW(R_INFO)(0, R_X86_64_RELATIVE);
+ qrel->r_addend = *(long long *)ptr + val;
+ qrel++;
+ }
+ }
+ *(long long *)ptr += val;
+ break;
+ case R_X86_64_32:
+ case R_X86_64_32S:
+ if (s1->output_type == TCC_OUTPUT_DLL) {
+ /* XXX: this logic may depend on TCC's codegen
+ now TCC uses R_X86_64_32 even for a 64bit pointer */
+ qrel->r_info = ELFW(R_INFO)(0, R_X86_64_RELATIVE);
+ qrel->r_addend = *(int *)ptr + val;
+ qrel++;
+ }
+ *(int *)ptr += val;
+ break;
+
+ case R_X86_64_PC32:
+ if (s1->output_type == TCC_OUTPUT_DLL) {
+ /* DLL relocation */
+ esym_index = s1->symtab_to_dynsym[sym_index];
+ if (esym_index) {
+ qrel->r_offset = rel->r_offset;
+ qrel->r_info = ELFW(R_INFO)(esym_index, R_X86_64_PC32);
+ qrel->r_addend = *(int *)ptr;
+ qrel++;
+ break;
+ }
+ }
+ goto plt32pc32;
+
+ case R_X86_64_PLT32:
+ /* We've put the PLT slot offset into r_addend when generating
+ it, and that's what we must use as relocation value (adjusted
+ by section offset of course). */
+ val = s1->plt->sh_addr + rel->r_addend;
+ /* fallthrough. */
+
+ plt32pc32:
+ {
+ long long diff;
+ diff = (long long)val - addr;
+ if (diff < -2147483648LL || diff > 2147483647LL) {
+ tcc_error("internal error: relocation failed");
+ }
+ *(int *)ptr += diff;
+ }
+ break;
+ case R_X86_64_GLOB_DAT:
+ case R_X86_64_JUMP_SLOT:
+ /* They don't need addend */
+ *(addr_t *)ptr = val - rel->r_addend;
+ break;
+ case R_X86_64_GOTPCREL:
+ *(int *)ptr += (s1->got->sh_addr - addr +
+ s1->sym_attrs[sym_index].got_offset - 4);
+ break;
+ case R_X86_64_GOTTPOFF:
+ *(int *)ptr += val - s1->got->sh_addr;
+ break;
+ case R_X86_64_GOT32:
+ /* we load the got offset */
+ *(int *)ptr += s1->sym_attrs[sym_index].got_offset;
+ break;
+#else
+#error unsupported processor
+#endif
+ }
+ }
+ /* if the relocation is allocated, we change its symbol table */
+ if (sr->sh_flags & SHF_ALLOC)
+ sr->link = s1->dynsym;
+}
+
+/* relocate relocation table in 'sr' */
+static void relocate_rel(TCCState *s1, Section *sr)
+{
+ Section *s;
+ ElfW_Rel *rel;
+
+ s = s1->sections[sr->sh_info];
+ for_each_elem(sr, 0, rel, ElfW_Rel)
+ rel->r_offset += s->sh_addr;
+}
+
+/* count the number of dynamic relocations so that we can reserve
+ their space */
+static int prepare_dynamic_rel(TCCState *s1, Section *sr)
+{
+ ElfW_Rel *rel;
+ int sym_index, esym_index, type, count;
+
+ count = 0;
+ for_each_elem(sr, 0, rel, ElfW_Rel) {
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ type = ELFW(R_TYPE)(rel->r_info);
+ switch(type) {
+#if defined(TCC_TARGET_I386)
+ case R_386_32:
+#elif defined(TCC_TARGET_X86_64)
+ case R_X86_64_32:
+ case R_X86_64_32S:
+ case R_X86_64_64:
+#endif
+ count++;
+ break;
+#if defined(TCC_TARGET_I386)
+ case R_386_PC32:
+#elif defined(TCC_TARGET_X86_64)
+ case R_X86_64_PC32:
+#endif
+ esym_index = s1->symtab_to_dynsym[sym_index];
+ if (esym_index)
+ count++;
+ break;
+ default:
+ break;
+ }
+ }
+ if (count) {
+ /* allocate the section */
+ sr->sh_flags |= SHF_ALLOC;
+ sr->sh_size = count * sizeof(ElfW_Rel);
+ }
+ return count;
+}
+
+static struct sym_attr *alloc_sym_attr(TCCState *s1, int index)
+{
+ int n;
+ struct sym_attr *tab;
+
+ if (index >= s1->nb_sym_attrs) {
+ /* find immediately bigger power of 2 and reallocate array */
+ n = 1;
+ while (index >= n)
+ n *= 2;
+ tab = tcc_realloc(s1->sym_attrs, n * sizeof(*s1->sym_attrs));
+ s1->sym_attrs = tab;
+ memset(s1->sym_attrs + s1->nb_sym_attrs, 0,
+ (n - s1->nb_sym_attrs) * sizeof(*s1->sym_attrs));
+ s1->nb_sym_attrs = n;
+ }
+ return &s1->sym_attrs[index];
+}
+
+/* XXX: suppress that */
+static void put32(unsigned char *p, uint32_t val)
+{
+ p[0] = val;
+ p[1] = val >> 8;
+ p[2] = val >> 16;
+ p[3] = val >> 24;
+}
+
+#if defined(TCC_TARGET_I386) || defined(TCC_TARGET_ARM) || \
+ defined(TCC_TARGET_ARM64) || defined(TCC_TARGET_X86_64)
+static uint32_t get32(unsigned char *p)
+{
+ return p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
+}
+#endif
+
+static void build_got(TCCState *s1)
+{
+ unsigned char *ptr;
+
+ /* if no got, then create it */
+ s1->got = new_section(s1, ".got", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
+ s1->got->sh_entsize = 4;
+ add_elf_sym(symtab_section, 0, 4, ELFW(ST_INFO)(STB_GLOBAL, STT_OBJECT),
+ 0, s1->got->sh_num, "_GLOBAL_OFFSET_TABLE_");
+ ptr = section_ptr_add(s1->got, 3 * PTR_SIZE);
+#if PTR_SIZE == 4
+ /* keep space for _DYNAMIC pointer, if present */
+ put32(ptr, 0);
+ /* two dummy got entries */
+ put32(ptr + 4, 0);
+ put32(ptr + 8, 0);
+#else
+ /* keep space for _DYNAMIC pointer, if present */
+ put32(ptr, 0);
+ put32(ptr + 4, 0);
+ /* two dummy got entries */
+ put32(ptr + 8, 0);
+ put32(ptr + 12, 0);
+ put32(ptr + 16, 0);
+ put32(ptr + 20, 0);
+#endif
+}
+
+/* put a got or plt entry corresponding to a symbol in symtab_section. 'size'
+ and 'info' can be modifed if more precise info comes from the DLL.
+ Returns offset of GOT or PLT slot. */
+static unsigned long put_got_entry(TCCState *s1,
+ int reloc_type, unsigned long size, int info,
+ int sym_index)
+{
+ int index, need_plt_entry;
+ const char *name;
+ ElfW(Sym) *sym;
+ unsigned long offset;
+ int *ptr;
+ struct sym_attr *symattr;
+
+ if (!s1->got)
+ build_got(s1);
+
+ need_plt_entry =
+#ifdef TCC_TARGET_X86_64
+ (reloc_type == R_X86_64_JUMP_SLOT);
+#elif defined(TCC_TARGET_I386)
+ (reloc_type == R_386_JMP_SLOT);
+#elif defined(TCC_TARGET_ARM)
+ (reloc_type == R_ARM_JUMP_SLOT);
+#elif defined(TCC_TARGET_ARM64)
+ (reloc_type == R_AARCH64_JUMP_SLOT);
+#else
+ 0;
+#endif
+
+ if (need_plt_entry && !s1->plt) {
+ /* add PLT */
+ s1->plt = new_section(s1, ".plt", SHT_PROGBITS,
+ SHF_ALLOC | SHF_EXECINSTR);
+ s1->plt->sh_entsize = 4;
+ }
+
+ /* If a got/plt entry already exists for that symbol, no need to add one */
+ if (sym_index < s1->nb_sym_attrs) {
+ if (need_plt_entry && s1->sym_attrs[sym_index].plt_offset)
+ return s1->sym_attrs[sym_index].plt_offset;
+ else if (!need_plt_entry && s1->sym_attrs[sym_index].got_offset)
+ return s1->sym_attrs[sym_index].got_offset;
+ }
+
+ symattr = alloc_sym_attr(s1, sym_index);
+
+ /* Only store the GOT offset if it's not generated for the PLT entry. */
+ if (!need_plt_entry)
+ symattr->got_offset = s1->got->data_offset;
+
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ name = (char *) symtab_section->link->data + sym->st_name;
+ offset = sym->st_value;
+#if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
+ if (need_plt_entry) {
+ Section *plt;
+ uint8_t *p;
+ int modrm;
+ unsigned long relofs;
+
+#if defined(TCC_OUTPUT_DLL_WITH_PLT)
+ modrm = 0x25;
+#else
+ /* if we build a DLL, we add a %ebx offset */
+ if (s1->output_type == TCC_OUTPUT_DLL)
+ modrm = 0xa3;
+ else
+ modrm = 0x25;
+#endif
+
+ /* add a PLT entry */
+ plt = s1->plt;
+ if (plt->data_offset == 0) {
+ /* first plt entry */
+ p = section_ptr_add(plt, 16);
+ p[0] = 0xff; /* pushl got + PTR_SIZE */
+ p[1] = modrm + 0x10;
+ put32(p + 2, PTR_SIZE);
+ p[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
+ p[7] = modrm;
+ put32(p + 8, PTR_SIZE * 2);
+ }
+
+ /* The PLT slot refers to the relocation entry it needs
+ via offset. The reloc entry is created below, so its
+ offset is the current data_offset. */
+ relofs = s1->got->reloc ? s1->got->reloc->data_offset : 0;
+ symattr->plt_offset = plt->data_offset;
+ p = section_ptr_add(plt, 16);
+ p[0] = 0xff; /* jmp *(got + x) */
+ p[1] = modrm;
+ put32(p + 2, s1->got->data_offset);
+ p[6] = 0x68; /* push $xxx */
+#ifdef TCC_TARGET_X86_64
+ /* On x86-64, the relocation is referred to by _index_. */
+ put32(p + 7, relofs / sizeof (ElfW_Rel));
+#else
+ put32(p + 7, relofs);
+#endif
+ p[11] = 0xe9; /* jmp plt_start */
+ put32(p + 12, -(plt->data_offset));
+
+ /* If this was an UNDEF symbol set the offset in the
+ dynsymtab to the PLT slot, so that PC32 relocs to it
+ can be resolved. */
+ if (sym->st_shndx == SHN_UNDEF)
+ offset = plt->data_offset - 16;
+ }
+#elif defined(TCC_TARGET_ARM)
+ if (need_plt_entry) {
+ Section *plt;
+ uint8_t *p;
+
+ /* if we build a DLL, we add a %ebx offset */
+ if (s1->output_type == TCC_OUTPUT_DLL)
+ tcc_error("DLLs unimplemented!");
+
+ /* add a PLT entry */
+ plt = s1->plt;
+ if (plt->data_offset == 0) {
+ /* first plt entry */
+ p = section_ptr_add(plt, 16);
+ put32(p, 0xe52de004); /* push {lr} */
+ put32(p+4, 0xe59fe010); /* ldr lr, [pc, #16] */
+ put32(p+8, 0xe08fe00e); /* add lr, pc, lr */
+ put32(p+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
+ }
+
+ symattr->plt_offset = plt->data_offset;
+ if (symattr->plt_thumb_stub) {
+ p = section_ptr_add(plt, 20);
+ put32(p, 0x4778); /* bx pc */
+ put32(p+2, 0x46c0); /* nop */
+ p += 4;
+ } else
+ p = section_ptr_add(plt, 16);
+ put32(p, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
+ put32(p+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
+ put32(p+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
+ put32(p+12, s1->got->data_offset); /* GOT entry off once patched */
+
+ /* the symbol is modified so that it will be relocated to
+ the PLT */
+ if (sym->st_shndx == SHN_UNDEF)
+ offset = plt->data_offset - 16;
+ }
+#elif defined(TCC_TARGET_ARM64)
+ if (need_plt_entry) {
+ Section *plt;
+ uint8_t *p;
+
+ if (s1->output_type == TCC_OUTPUT_DLL)
+ tcc_error("DLLs unimplemented!");
+
+ plt = s1->plt;
+ if (plt->data_offset == 0)
+ section_ptr_add(plt, 32);
+ symattr->plt_offset = plt->data_offset;
+ p = section_ptr_add(plt, 16);
+ put32(p, s1->got->data_offset);
+ put32(p + 4, (uint64_t)s1->got->data_offset >> 32);
+
+ if (sym->st_shndx == SHN_UNDEF)
+ offset = plt->data_offset - 16;
+ }
+#elif defined(TCC_TARGET_C67)
+ if (s1->dynsym) {
+ tcc_error("C67 got not implemented");
+ }
+#else
+#error unsupported CPU
+#endif
+ if (s1->dynsym) {
+ /* XXX This might generate multiple syms for name. */
+ index = put_elf_sym(s1->dynsym, offset,
+ size, info, 0, sym->st_shndx, name);
+ /* Create the relocation (it's against the GOT for PLT
+ and GOT relocs). */
+ put_elf_reloc(s1->dynsym, s1->got,
+ s1->got->data_offset,
+ reloc_type, index);
+ } else {
+ /* Without .dynsym (i.e. static link or memory output) we
+ still need relocs against the generated got, so as to fill
+ the entries with the symbol values (determined later). */
+ put_elf_reloc(symtab_section, s1->got,
+ s1->got->data_offset,
+ reloc_type, sym_index);
+ }
+ /* And now create the GOT slot itself. */
+ ptr = section_ptr_add(s1->got, PTR_SIZE);
+ *ptr = 0;
+ if (need_plt_entry)
+ return symattr->plt_offset;
+ else
+ return symattr->got_offset;
+}
+
+/* build GOT and PLT entries */
+ST_FUNC void build_got_entries(TCCState *s1)
+{
+ Section *s;
+ ElfW_Rel *rel;
+ ElfW(Sym) *sym;
+ int i, type, reloc_type, sym_index;
+
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[i];
+ if (s->sh_type != SHT_RELX)
+ continue;
+ /* no need to handle got relocations */
+ if (s->link != symtab_section)
+ continue;
+ for_each_elem(s, 0, rel, ElfW_Rel) {
+ type = ELFW(R_TYPE)(rel->r_info);
+ switch(type) {
+#if defined(TCC_TARGET_I386)
+ case R_386_GOT32:
+ case R_386_GOTOFF:
+ case R_386_GOTPC:
+ case R_386_PLT32:
+ if (!s1->got)
+ build_got(s1);
+ if (type == R_386_GOT32 || type == R_386_PLT32) {
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ /* look at the symbol got offset. If none, then add one */
+ if (type == R_386_GOT32)
+ reloc_type = R_386_GLOB_DAT;
+ else
+ reloc_type = R_386_JMP_SLOT;
+ put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
+ sym_index);
+ }
+ break;
+#elif defined(TCC_TARGET_ARM)
+ case R_ARM_PC24:
+ case R_ARM_CALL:
+ case R_ARM_JUMP24:
+ case R_ARM_GOT32:
+ case R_ARM_GOTOFF:
+ case R_ARM_GOTPC:
+ case R_ARM_PLT32:
+ if (!s1->got)
+ build_got(s1);
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ if (type != R_ARM_GOTOFF && type != R_ARM_GOTPC
+ && sym->st_shndx == SHN_UNDEF) {
+ unsigned long ofs;
+ /* look at the symbol got offset. If none, then add one */
+ if (type == R_ARM_GOT32)
+ reloc_type = R_ARM_GLOB_DAT;
+ else
+ reloc_type = R_ARM_JUMP_SLOT;
+ ofs = put_got_entry(s1, reloc_type, sym->st_size,
+ sym->st_info, sym_index);
+#ifdef DEBUG_RELOC
+ printf ("maybegot: %s, %d, %d --> ofs=0x%x\n",
+ (char *) symtab_section->link->data + sym->st_name,
+ type, sym->st_shndx, ofs);
+#endif
+ if (type != R_ARM_GOT32) {
+ addr_t *ptr = (addr_t*)(s1->sections[s->sh_info]->data
+ + rel->r_offset);
+ /* x must be signed! */
+ int x = *ptr & 0xffffff;
+ x = (x << 8) >> 8;
+ x <<= 2;
+ x += ofs;
+ x >>= 2;
+#ifdef DEBUG_RELOC
+ printf ("insn=0x%x --> 0x%x (x==0x%x)\n", *ptr,
+ (*ptr & 0xff000000) | x, x);
+#endif
+ *ptr = (*ptr & 0xff000000) | x;
+ }
+ }
+ break;
+ case R_ARM_THM_JUMP24:
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ /* We are relocating a jump from thumb code to arm code */
+ if (sym->st_shndx != SHN_UNDEF && !(sym->st_value & 1)) {
+ int index;
+ uint8_t *p;
+ char *name, buf[1024];
+ Section *text_section;
+
+ name = (char *) symtab_section->link->data + sym->st_name;
+ text_section = s1->sections[sym->st_shndx];
+ /* Modify reloc to target a thumb stub to switch to ARM */
+ snprintf(buf, sizeof(buf), "%s_from_thumb", name);
+ index = put_elf_sym(symtab_section,
+ text_section->data_offset + 1,
+ sym->st_size, sym->st_info, 0,
+ sym->st_shndx, buf);
+ rel->r_info = ELFW(R_INFO)(index, type);
+ /* Create a thumb stub fonction to switch to ARM mode */
+ put_elf_reloc(symtab_section, text_section,
+ text_section->data_offset + 4, R_ARM_JUMP24,
+ sym_index);
+ p = section_ptr_add(text_section, 8);
+ put32(p, 0x4778); /* bx pc */
+ put32(p+2, 0x46c0); /* nop */
+ put32(p+4, 0xeafffffe); /* b $sym */
+ }
+#elif defined(TCC_TARGET_ARM64)
+ //xx Other cases may be required here:
+ case R_AARCH64_ADR_GOT_PAGE:
+ case R_AARCH64_LD64_GOT_LO12_NC:
+ if (!s1->got)
+ build_got(s1);
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ reloc_type = R_AARCH64_GLOB_DAT;
+ put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
+ sym_index);
+ break;
+
+ case R_AARCH64_JUMP26:
+ case R_AARCH64_CALL26:
+ if (!s1->got)
+ build_got(s1);
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ if (sym->st_shndx == SHN_UNDEF) {
+ unsigned long ofs;
+ reloc_type = R_AARCH64_JUMP_SLOT;
+ ofs = put_got_entry(s1, reloc_type, sym->st_size,
+ sym->st_info, sym_index);
+ /* We store the place of the generated PLT slot
+ in our addend. */
+ rel->r_addend += ofs;
+ }
+ break;
+#elif defined(TCC_TARGET_C67)
+ case R_C60_GOT32:
+ case R_C60_GOTOFF:
+ case R_C60_GOTPC:
+ case R_C60_PLT32:
+ if (!s1->got)
+ build_got(s1);
+ if (type == R_C60_GOT32 || type == R_C60_PLT32) {
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ /* look at the symbol got offset. If none, then add one */
+ if (type == R_C60_GOT32)
+ reloc_type = R_C60_GLOB_DAT;
+ else
+ reloc_type = R_C60_JMP_SLOT;
+ put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
+ sym_index);
+ }
+ break;
+#elif defined(TCC_TARGET_X86_64)
+ case R_X86_64_GOT32:
+ case R_X86_64_GOTTPOFF:
+ case R_X86_64_GOTPCREL:
+ case R_X86_64_PLT32:
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ if (type == R_X86_64_PLT32 &&
+ ELFW(ST_VISIBILITY)(sym->st_other) != STV_DEFAULT)
+ {
+ rel->r_info = ELFW(R_INFO)(sym_index, R_X86_64_PC32);
+ break;
+ }
+
+ if (!s1->got)
+ build_got(s1);
+ if (type == R_X86_64_GOT32 || type == R_X86_64_GOTPCREL ||
+ type == R_X86_64_PLT32) {
+ unsigned long ofs;
+ /* look at the symbol got offset. If none, then add one */
+ if (type == R_X86_64_GOT32 || type == R_X86_64_GOTPCREL)
+ reloc_type = R_X86_64_GLOB_DAT;
+ else
+ reloc_type = R_X86_64_JUMP_SLOT;
+ ofs = put_got_entry(s1, reloc_type, sym->st_size,
+ sym->st_info, sym_index);
+ if (type == R_X86_64_PLT32)
+ /* We store the place of the generated PLT slot
+ in our addend. */
+ rel->r_addend += ofs;
+ }
+ break;
+#else
+#error unsupported CPU
+#endif
+ default:
+ break;
+ }
+ }
+ }
+}
+
+ST_FUNC Section *new_symtab(TCCState *s1,
+ const char *symtab_name, int sh_type, int sh_flags,
+ const char *strtab_name,
+ const char *hash_name, int hash_sh_flags)
+{
+ Section *symtab, *strtab, *hash;
+ int *ptr, nb_buckets;
+
+ symtab = new_section(s1, symtab_name, sh_type, sh_flags);
+ symtab->sh_entsize = sizeof(ElfW(Sym));
+ strtab = new_section(s1, strtab_name, SHT_STRTAB, sh_flags);
+ put_elf_str(strtab, "");
+ symtab->link = strtab;
+ put_elf_sym(symtab, 0, 0, 0, 0, 0, NULL);
+
+ nb_buckets = 1;
+
+ hash = new_section(s1, hash_name, SHT_HASH, hash_sh_flags);
+ hash->sh_entsize = sizeof(int);
+ symtab->hash = hash;
+ hash->link = symtab;
+
+ ptr = section_ptr_add(hash, (2 + nb_buckets + 1) * sizeof(int));
+ ptr[0] = nb_buckets;
+ ptr[1] = 1;
+ memset(ptr + 2, 0, (nb_buckets + 1) * sizeof(int));
+ return symtab;
+}
+
+/* put dynamic tag */
+static void put_dt(Section *dynamic, int dt, addr_t val)
+{
+ ElfW(Dyn) *dyn;
+ dyn = section_ptr_add(dynamic, sizeof(ElfW(Dyn)));
+ dyn->d_tag = dt;
+ dyn->d_un.d_val = val;
+}
+
+static void add_init_array_defines(TCCState *s1, const char *section_name)
+{
+ Section *s;
+ long end_offset;
+ char sym_start[1024];
+ char sym_end[1024];
+
+ snprintf(sym_start, sizeof(sym_start), "__%s_start", section_name + 1);
+ snprintf(sym_end, sizeof(sym_end), "__%s_end", section_name + 1);
+
+ s = find_section(s1, section_name);
+ if (!s) {
+ end_offset = 0;
+ s = data_section;
+ } else {
+ end_offset = s->data_offset;
+ }
+
+ add_elf_sym(symtab_section,
+ 0, 0,
+ ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
+ s->sh_num, sym_start);
+ add_elf_sym(symtab_section,
+ end_offset, 0,
+ ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
+ s->sh_num, sym_end);
+}
+
+static int tcc_add_support(TCCState *s1, const char *filename)
+{
+ char buf[1024];
+ snprintf(buf, sizeof(buf), "%s/%s/%s", s1->tcc_lib_path,
+ /* an cpu specific path inside tcc_lib_path, mainly for keeping libtcc1.a */
+ #ifdef TCC_TARGET_I386
+ "i386"
+ #endif
+ #ifdef TCC_TARGET_X86_64
+ "x86-64"
+ #endif
+ #ifdef TCC_TARGET_ARM
+ "arm"
+ #endif
+ #ifdef TCC_TARGET_ARM64
+ "arm64"
+ #endif
+ #ifdef TCC_TARGET_C67
+ "C67"
+ #endif
+ ,filename);
+
+ return tcc_add_file(s1, buf, TCC_FILETYPE_BINARY);
+}
+
+ST_FUNC void tcc_add_bcheck(TCCState *s1)
+{
+#ifdef CONFIG_TCC_BCHECK
+ addr_t *ptr;
+
+ if (0 == s1->do_bounds_check)
+ return;
+
+ /* XXX: add an object file to do that */
+ ptr = section_ptr_add(bounds_section, sizeof(*ptr));
+ *ptr = 0;
+ add_elf_sym(symtab_section, 0, 0,
+ ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
+ bounds_section->sh_num, "__bounds_start");
+ if (s1->output_type != TCC_OUTPUT_MEMORY) {
+ /* add 'call __bound_init()' in .init section */
+
+ /* XXX not called on MSYS, reason is unknown. For this
+ case a call to __bound_init is performed in bcheck.c
+ when __bound_ptr_add, __bound_new_region,
+ __bound_delete_region called */
+
+ int sym_index = find_elf_sym(symtab_section, "__bound_init");
+ if (sym_index) {
+ Section *init_section = find_section(s1, ".init");
+ unsigned char *pinit = section_ptr_add(init_section, 5);
+ pinit[0] = 0xe8;
+ put32(pinit + 1, -4);
+ put_elf_reloc(symtab_section, init_section,
+ init_section->data_offset - 4, R_386_PC32, sym_index);
+ }
+ else
+ tcc_warning("__bound_init not defined");
+ }
+#endif
+}
+
+/* add tcc runtime libraries */
+ST_FUNC void tcc_add_runtime(TCCState *s1)
+{
+ tcc_add_pragma_libs(s1);
+
+ /* add libc */
+ if (!s1->nostdlib) {
+ tcc_add_library(s1, "c");
+#ifdef CONFIG_USE_LIBGCC
+ if (!s1->static_link) {
+ tcc_add_file(s1, TCC_LIBGCC, TCC_FILETYPE_BINARY);
+ }
+#endif
+ tcc_add_support(s1, "libtcc1.a");
+ }
+
+ /* tcc_add_bcheck tries to relocate a call to __bound_init in _init so
+ libtcc1.a must be loaded before for __bound_init to be defined and
+ crtn.o must be loaded after to not finalize _init too early. */
+ tcc_add_bcheck(s1);
+
+ if (!s1->nostdlib) {
+ /* add crt end if not memory output */
+ if (s1->output_type != TCC_OUTPUT_MEMORY)
+ tcc_add_crt(s1, "crtn.o");
+ }
+}
+
+/* add various standard linker symbols (must be done after the
+ sections are filled (for example after allocating common
+ symbols)) */
+ST_FUNC void tcc_add_linker_symbols(TCCState *s1)
+{
+ char buf[1024];
+ int i;
+ Section *s;
+
+ add_elf_sym(symtab_section,
+ text_section->data_offset, 0,
+ ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
+ text_section->sh_num, "_etext");
+ add_elf_sym(symtab_section,
+ data_section->data_offset, 0,
+ ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
+ data_section->sh_num, "_edata");
+ add_elf_sym(symtab_section,
+ bss_section->data_offset, 0,
+ ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
+ bss_section->sh_num, "_end");
+ /* horrible new standard ldscript defines */
+ add_init_array_defines(s1, ".preinit_array");
+ add_init_array_defines(s1, ".init_array");
+ add_init_array_defines(s1, ".fini_array");
+
+ /* add start and stop symbols for sections whose name can be
+ expressed in C */
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[i];
+ if (s->sh_type == SHT_PROGBITS &&
+ (s->sh_flags & SHF_ALLOC)) {
+ const char *p;
+ int ch;
+
+ /* check if section name can be expressed in C */
+ p = s->name;
+ for(;;) {
+ ch = *p;
+ if (!ch)
+ break;
+ if (!isid(ch) && !isnum(ch))
+ goto next_sec;
+ p++;
+ }
+ snprintf(buf, sizeof(buf), "__start_%s", s->name);
+ add_elf_sym(symtab_section,
+ 0, 0,
+ ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
+ s->sh_num, buf);
+ snprintf(buf, sizeof(buf), "__stop_%s", s->name);
+ add_elf_sym(symtab_section,
+ s->data_offset, 0,
+ ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
+ s->sh_num, buf);
+ }
+ next_sec: ;
+ }
+}
+
+static void tcc_output_binary(TCCState *s1, FILE *f,
+ const int *sec_order)
+{
+ Section *s;
+ int i, offset, size;
+
+ offset = 0;
+ for(i=1;i<s1->nb_sections;i++) {
+ s = s1->sections[sec_order[i]];
+ if (s->sh_type != SHT_NOBITS &&
+ (s->sh_flags & SHF_ALLOC)) {
+ while (offset < s->sh_offset) {
+ fputc(0, f);
+ offset++;
+ }
+ size = s->sh_size;
+ fwrite(s->data, 1, size, f);
+ offset += size;
+ }
+ }
+}
+
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+#define HAVE_PHDR 1
+#define EXTRA_RELITEMS 14
+
+/* move the relocation value from .dynsym to .got */
+void patch_dynsym_undef(TCCState *s1, Section *s)
+{
+ uint32_t *gotd = (void *)s1->got->data;
+ ElfW(Sym) *sym;
+
+ gotd += 3; /* dummy entries in .got */
+ /* relocate symbols in .dynsym */
+ for_each_elem(s, 1, sym, ElfW(Sym)) {
+ if (sym->st_shndx == SHN_UNDEF) {
+ *gotd++ = sym->st_value + 6; /* XXX 6 is magic ? */
+ sym->st_value = 0;
+ }
+ }
+}
+#else
+#define HAVE_PHDR 1
+#define EXTRA_RELITEMS 9
+
+/* zero plt offsets of weak symbols in .dynsym */
+void patch_dynsym_undef(TCCState *s1, Section *s)
+{
+ ElfW(Sym) *sym;
+
+ for_each_elem(s, 1, sym, ElfW(Sym))
+ if (sym->st_shndx == SHN_UNDEF && ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
+ sym->st_value = 0;
+}
+#endif
+
+ST_FUNC void fill_got_entry(TCCState *s1, ElfW_Rel *rel)
+{
+ int sym_index = ELFW(R_SYM) (rel->r_info);
+ ElfW(Sym) *sym = &((ElfW(Sym) *) symtab_section->data)[sym_index];
+ unsigned long offset;
+
+ if (sym_index >= s1->nb_sym_attrs)
+ return;
+ offset = s1->sym_attrs[sym_index].got_offset;
+ section_reserve(s1->got, offset + PTR_SIZE);
+#ifdef TCC_TARGET_X86_64
+ /* only works for x86-64 */
+ put32(s1->got->data + offset + 4, sym->st_value >> 32);
+#endif
+ put32(s1->got->data + offset, sym->st_value & 0xffffffff);
+}
+
+/* Perform relocation to GOT or PLT entries */
+ST_FUNC void fill_got(TCCState *s1)
+{
+ Section *s;
+ ElfW_Rel *rel;
+ int i;
+
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[i];
+ if (s->sh_type != SHT_RELX)
+ continue;
+ /* no need to handle got relocations */
+ if (s->link != symtab_section)
+ continue;
+ for_each_elem(s, 0, rel, ElfW_Rel) {
+ switch (ELFW(R_TYPE) (rel->r_info)) {
+ case R_X86_64_GOT32:
+ case R_X86_64_GOTPCREL:
+ case R_X86_64_PLT32:
+ fill_got_entry(s1, rel);
+ break;
+ }
+ }
+ }
+}
+
+/* Bind symbols of executable: resolve undefined symbols from exported symbols
+ in shared libraries and export non local defined symbols to shared libraries
+ if -rdynamic switch was given on command line */
+static void bind_exe_dynsyms(TCCState *s1)
+{
+ const char *name;
+ int sym_index, index;
+ ElfW(Sym) *sym, *esym;
+ int type;
+
+ /* Resolve undefined symbols from dynamic symbols. When there is a match:
+ - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
+ - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
+ for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
+ if (sym->st_shndx == SHN_UNDEF) {
+ name = (char *) symtab_section->link->data + sym->st_name;
+ sym_index = find_elf_sym(s1->dynsymtab_section, name);
+ if (sym_index) {
+ esym = &((ElfW(Sym) *)s1->dynsymtab_section->data)[sym_index];
+ type = ELFW(ST_TYPE)(esym->st_info);
+ if ((type == STT_FUNC) || (type == STT_GNU_IFUNC)) {
+ /* Indirect functions shall have STT_FUNC type in executable
+ * dynsym section. Indeed, a dlsym call following a lazy
+ * resolution would pick the symbol value from the
+ * executable dynsym entry which would contain the address
+ * of the function wanted by the caller of dlsym instead of
+ * the address of the function that would return that
+ * address */
+ put_got_entry(s1, R_JMP_SLOT, esym->st_size,
+ ELFW(ST_INFO)(STB_GLOBAL,STT_FUNC),
+ sym - (ElfW(Sym) *)symtab_section->data);
+ } else if (type == STT_OBJECT) {
+ unsigned long offset;
+ ElfW(Sym) *dynsym;
+ offset = bss_section->data_offset;
+ /* XXX: which alignment ? */
+ offset = (offset + 16 - 1) & -16;
+ index = put_elf_sym(s1->dynsym, offset, esym->st_size,
+ esym->st_info, 0, bss_section->sh_num,
+ name);
+ /* Ensure R_COPY works for weak symbol aliases */
+ if (ELFW(ST_BIND)(esym->st_info) == STB_WEAK) {
+ for_each_elem(s1->dynsymtab_section, 1, dynsym, ElfW(Sym)) {
+ if ((dynsym->st_value == esym->st_value)
+ && (ELFW(ST_BIND)(dynsym->st_info) == STB_GLOBAL)) {
+ char *dynname = (char *) s1->dynsymtab_section->link->data
+ + dynsym->st_name;
+ put_elf_sym(s1->dynsym, offset, dynsym->st_size,
+ dynsym->st_info, 0,
+ bss_section->sh_num, dynname);
+ break;
+ }
+ }
+ }
+ put_elf_reloc(s1->dynsym, bss_section,
+ offset, R_COPY, index);
+ offset += esym->st_size;
+ bss_section->data_offset = offset;
+ }
+ } else {
+ /* STB_WEAK undefined symbols are accepted */
+ /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
+ if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK ||
+ !strcmp(name, "_fp_hw")) {
+ } else {
+ tcc_error_noabort("undefined symbol '%s'", name);
+ }
+ }
+ } else if (s1->rdynamic && ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
+ /* if -rdynamic option, then export all non local symbols */
+ name = (char *) symtab_section->link->data + sym->st_name;
+ put_elf_sym(s1->dynsym, sym->st_value, sym->st_size, sym->st_info,
+ 0, sym->st_shndx, name);
+ }
+ }
+}
+
+/* Bind symbols of libraries: export non local symbols of executable that
+ resolve undefined symbols of shared libraries */
+static void bind_libs_dynsyms(TCCState *s1)
+{
+ const char *name;
+ int sym_index;
+ ElfW(Sym) *sym, *esym;
+
+ /* now look at unresolved dynamic symbols and export
+ corresponding symbol */
+ for_each_elem(s1->dynsymtab_section, 1, esym, ElfW(Sym)) {
+ name = (char *) s1->dynsymtab_section->link->data + esym->st_name;
+ sym_index = find_elf_sym(symtab_section, name);
+ if (sym_index) {
+ /* XXX: avoid adding a symbol if already present because of
+ -rdynamic ? */
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ if (sym->st_shndx != SHN_UNDEF)
+ put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
+ sym->st_info, 0, sym->st_shndx, name);
+ } else if (esym->st_shndx == SHN_UNDEF) {
+ /* weak symbols can stay undefined */
+ if (ELFW(ST_BIND)(esym->st_info) != STB_WEAK)
+ tcc_warning("undefined dynamic symbol '%s'", name);
+ }
+ }
+}
+
+/* Export all non local symbols (for shared libraries) */
+static void export_global_syms(TCCState *s1)
+{
+ int nb_syms, dynindex, index;
+ const char *name;
+ ElfW(Sym) *sym;
+
+ nb_syms = symtab_section->data_offset / sizeof(ElfW(Sym));
+ s1->symtab_to_dynsym = tcc_mallocz(sizeof(int) * nb_syms);
+ for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
+ if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
+ name = (char *) symtab_section->link->data + sym->st_name;
+ dynindex = put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
+ sym->st_info, 0, sym->st_shndx, name);
+ index = sym - (ElfW(Sym) *) symtab_section->data;
+ s1->symtab_to_dynsym[index] = dynindex;
+ }
+ }
+}
+
+/* relocate the PLT: compute addresses and offsets in the PLT now that final
+ address for PLT and GOT are known (see fill_program_header) */
+ST_FUNC void relocate_plt(TCCState *s1)
+{
+ uint8_t *p, *p_end;
+
+ if (!s1->plt)
+ return;
+
+ p = s1->plt->data;
+ p_end = p + s1->plt->data_offset;
+ if (p < p_end) {
+#if defined(TCC_TARGET_I386)
+ put32(p + 2, get32(p + 2) + s1->got->sh_addr);
+ put32(p + 8, get32(p + 8) + s1->got->sh_addr);
+ p += 16;
+ while (p < p_end) {
+ put32(p + 2, get32(p + 2) + s1->got->sh_addr);
+ p += 16;
+ }
+#elif defined(TCC_TARGET_X86_64)
+ int x = s1->got->sh_addr - s1->plt->sh_addr - 6;
+ put32(p + 2, get32(p + 2) + x);
+ put32(p + 8, get32(p + 8) + x - 6);
+ p += 16;
+ while (p < p_end) {
+ put32(p + 2, get32(p + 2) + x + s1->plt->data - p);
+ p += 16;
+ }
+#elif defined(TCC_TARGET_ARM)
+ int x;
+ x=s1->got->sh_addr - s1->plt->sh_addr - 12;
+ p += 16;
+ while (p < p_end) {
+ if (get32(p) == 0x46c04778) /* PLT Thumb stub present */
+ p += 4;
+ put32(p + 12, x + get32(p + 12) + s1->plt->data - p);
+ p += 16;
+ }
+#elif defined(TCC_TARGET_ARM64)
+ uint64_t plt = s1->plt->sh_addr;
+ uint64_t got = s1->got->sh_addr;
+ uint64_t off = (got >> 12) - (plt >> 12);
+ if ((off + ((uint32_t)1 << 20)) >> 21)
+ tcc_error("Failed relocating PLT (off=0x%lx, got=0x%lx, plt=0x%lx)", off, got, plt);
+ put32(p, 0xa9bf7bf0); // stp x16,x30,[sp,#-16]!
+ put32(p + 4, (0x90000010 | // adrp x16,...
+ (off & 0x1ffffc) << 3 | (off & 3) << 29));
+ put32(p + 8, (0xf9400211 | // ldr x17,[x16,#...]
+ (got & 0xff8) << 7));
+ put32(p + 12, (0x91000210 | // add x16,x16,#...
+ (got & 0xfff) << 10));
+ put32(p + 16, 0xd61f0220); // br x17
+ put32(p + 20, 0xd503201f); // nop
+ put32(p + 24, 0xd503201f); // nop
+ put32(p + 28, 0xd503201f); // nop
+ p += 32;
+ while (p < p_end) {
+ uint64_t pc = plt + (p - s1->plt->data);
+ uint64_t addr = got +
+ (get32(p) | (uint64_t)get32(p + 4) << 32);
+ uint32_t off = (addr >> 12) - (pc >> 12);
+ if ((off + ((uint32_t)1 << 20)) >> 21)
+ tcc_error("Failed relocating PLT (off=0x%lx, addr=0x%lx, pc=0x%lx)", off, addr, pc);
+ put32(p, (0x90000010 | // adrp x16,...
+ (off & 0x1ffffc) << 3 | (off & 3) << 29));
+ put32(p + 4, (0xf9400211 | // ldr x17,[x16,#...]
+ (addr & 0xff8) << 7));
+ put32(p + 8, (0x91000210 | // add x16,x16,#...
+ (addr & 0xfff) << 10));
+ put32(p + 12, 0xd61f0220); // br x17
+ p += 16;
+ }
+#elif defined(TCC_TARGET_C67)
+ /* XXX: TODO */
+#else
+#error unsupported CPU
+#endif
+ }
+}
+
+/* Allocate strings for section names and decide if an unallocated section
+ should be output.
+
+ NOTE: the strsec section comes last, so its size is also correct ! */
+static void alloc_sec_names(TCCState *s1, int file_type, Section *strsec)
+{
+ int i;
+ Section *s;
+
+ /* Allocate strings for section names */
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[i];
+ s->sh_name = put_elf_str(strsec, s->name);
+ /* when generating a DLL, we include relocations but we may
+ patch them */
+ if (file_type == TCC_OUTPUT_DLL &&
+ s->sh_type == SHT_RELX &&
+ !(s->sh_flags & SHF_ALLOC)) {
+ /* gr: avoid bogus relocs for empty (debug) sections */
+ if (s1->sections[s->sh_info]->sh_flags & SHF_ALLOC)
+ prepare_dynamic_rel(s1, s);
+ else if (s1->do_debug)
+ s->sh_size = s->data_offset;
+ } else if (s1->do_debug ||
+ file_type == TCC_OUTPUT_OBJ ||
+ file_type == TCC_OUTPUT_EXE ||
+ (s->sh_flags & SHF_ALLOC) ||
+ i == (s1->nb_sections - 1)) {
+ /* we output all sections if debug or object file */
+ s->sh_size = s->data_offset;
+ }
+ }
+}
+
+/* Info to be copied in dynamic section */
+struct dyn_inf {
+ Section *dynamic;
+ Section *dynstr;
+ unsigned long dyn_rel_off;
+ addr_t rel_addr;
+ addr_t rel_size;
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+ addr_t bss_addr;
+ addr_t bss_size;
+#endif
+};
+
+/* Assign sections to segments and decide how are sections laid out when loaded
+ in memory. This function also fills corresponding program headers. */
+static int layout_sections(TCCState *s1, ElfW(Phdr) *phdr, int phnum,
+ Section *interp, Section* strsec,
+ struct dyn_inf *dyninf, int *sec_order)
+{
+ int i, j, k, file_type, sh_order_index, file_offset;
+ unsigned long s_align;
+ long long tmp;
+ addr_t addr;
+ ElfW(Phdr) *ph;
+ Section *s;
+
+ file_type = s1->output_type;
+ sh_order_index = 1;
+ file_offset = 0;
+ if (s1->output_format == TCC_OUTPUT_FORMAT_ELF)
+ file_offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
+ s_align = ELF_PAGE_SIZE;
+ if (s1->section_align)
+ s_align = s1->section_align;
+
+ if (phnum > 0) {
+ if (s1->has_text_addr) {
+ int a_offset, p_offset;
+ addr = s1->text_addr;
+ /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
+ ELF_PAGE_SIZE */
+ a_offset = (int) (addr & (s_align - 1));
+ p_offset = file_offset & (s_align - 1);
+ if (a_offset < p_offset)
+ a_offset += s_align;
+ file_offset += (a_offset - p_offset);
+ } else {
+ if (file_type == TCC_OUTPUT_DLL)
+ addr = 0;
+ else
+ addr = ELF_START_ADDR;
+ /* compute address after headers */
+ addr += (file_offset & (s_align - 1));
+ }
+
+ ph = &phdr[0];
+ /* Leave one program headers for the program interpreter and one for
+ the program header table itself if needed. These are done later as
+ they require section layout to be done first. */
+ if (interp)
+ ph += 1 + HAVE_PHDR;
+
+ /* dynamic relocation table information, for .dynamic section */
+ dyninf->rel_addr = dyninf->rel_size = 0;
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+ dyninf->bss_addr = dyninf->bss_size = 0;
+#endif
+
+ for(j = 0; j < 2; j++) {
+ ph->p_type = PT_LOAD;
+ if (j == 0)
+ ph->p_flags = PF_R | PF_X;
+ else
+ ph->p_flags = PF_R | PF_W;
+ ph->p_align = s_align;
+
+ /* Decide the layout of sections loaded in memory. This must
+ be done before program headers are filled since they contain
+ info about the layout. We do the following ordering: interp,
+ symbol tables, relocations, progbits, nobits */
+ /* XXX: do faster and simpler sorting */
+ for(k = 0; k < 5; k++) {
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[i];
+ /* compute if section should be included */
+ if (j == 0) {
+ if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
+ SHF_ALLOC)
+ continue;
+ } else {
+ if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
+ (SHF_ALLOC | SHF_WRITE))
+ continue;
+ }
+ if (s == interp) {
+ if (k != 0)
+ continue;
+ } else if (s->sh_type == SHT_DYNSYM ||
+ s->sh_type == SHT_STRTAB ||
+ s->sh_type == SHT_HASH) {
+ if (k != 1)
+ continue;
+ } else if (s->sh_type == SHT_RELX) {
+ if (k != 2)
+ continue;
+ } else if (s->sh_type == SHT_NOBITS) {
+ if (k != 4)
+ continue;
+ } else {
+ if (k != 3)
+ continue;
+ }
+ sec_order[sh_order_index++] = i;
+
+ /* section matches: we align it and add its size */
+ tmp = addr;
+ addr = (addr + s->sh_addralign - 1) &
+ ~(s->sh_addralign - 1);
+ file_offset += (int) ( addr - tmp );
+ s->sh_offset = file_offset;
+ s->sh_addr = addr;
+
+ /* update program header infos */
+ if (ph->p_offset == 0) {
+ ph->p_offset = file_offset;
+ ph->p_vaddr = addr;
+ ph->p_paddr = ph->p_vaddr;
+ }
+ /* update dynamic relocation infos */
+ if (s->sh_type == SHT_RELX) {
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+ if (!strcmp(strsec->data + s->sh_name, ".rel.got")) {
+ dyninf->rel_addr = addr;
+ dyninf->rel_size += s->sh_size; /* XXX only first rel. */
+ }
+ if (!strcmp(strsec->data + s->sh_name, ".rel.bss")) {
+ dyninf->bss_addr = addr;
+ dyninf->bss_size = s->sh_size; /* XXX only first rel. */
+ }
+#else
+ if (dyninf->rel_size == 0)
+ dyninf->rel_addr = addr;
+ dyninf->rel_size += s->sh_size;
+#endif
+ }
+ addr += s->sh_size;
+ if (s->sh_type != SHT_NOBITS)
+ file_offset += s->sh_size;
+ }
+ }
+ if (j == 0) {
+ /* Make the first PT_LOAD segment include the program
+ headers itself (and the ELF header as well), it'll
+ come out with same memory use but will make various
+ tools like binutils strip work better. */
+ ph->p_offset &= ~(ph->p_align - 1);
+ ph->p_vaddr &= ~(ph->p_align - 1);
+ ph->p_paddr &= ~(ph->p_align - 1);
+ }
+ ph->p_filesz = file_offset - ph->p_offset;
+ ph->p_memsz = addr - ph->p_vaddr;
+ ph++;
+ if (j == 0) {
+ if (s1->output_format == TCC_OUTPUT_FORMAT_ELF) {
+ /* if in the middle of a page, we duplicate the page in
+ memory so that one copy is RX and the other is RW */
+ if ((addr & (s_align - 1)) != 0)
+ addr += s_align;
+ } else {
+ addr = (addr + s_align - 1) & ~(s_align - 1);
+ file_offset = (file_offset + s_align - 1) & ~(s_align - 1);
+ }
+ }
+ }
+ }
+
+ /* all other sections come after */
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[i];
+ if (phnum > 0 && (s->sh_flags & SHF_ALLOC))
+ continue;
+ sec_order[sh_order_index++] = i;
+
+ file_offset = (file_offset + s->sh_addralign - 1) &
+ ~(s->sh_addralign - 1);
+ s->sh_offset = file_offset;
+ if (s->sh_type != SHT_NOBITS)
+ file_offset += s->sh_size;
+ }
+
+ return file_offset;
+}
+
+static void fill_unloadable_phdr(ElfW(Phdr) *phdr, int phnum, Section *interp,
+ Section *dynamic)
+{
+ ElfW(Phdr) *ph;
+
+ /* if interpreter, then add corresponding program header */
+ if (interp) {
+ ph = &phdr[0];
+
+ if (HAVE_PHDR)
+ {
+ int len = phnum * sizeof(ElfW(Phdr));
+
+ ph->p_type = PT_PHDR;
+ ph->p_offset = sizeof(ElfW(Ehdr));
+ ph->p_vaddr = interp->sh_addr - len;
+ ph->p_paddr = ph->p_vaddr;
+ ph->p_filesz = ph->p_memsz = len;
+ ph->p_flags = PF_R | PF_X;
+ ph->p_align = 4; /* interp->sh_addralign; */
+ ph++;
+ }
+
+ ph->p_type = PT_INTERP;
+ ph->p_offset = interp->sh_offset;
+ ph->p_vaddr = interp->sh_addr;
+ ph->p_paddr = ph->p_vaddr;
+ ph->p_filesz = interp->sh_size;
+ ph->p_memsz = interp->sh_size;
+ ph->p_flags = PF_R;
+ ph->p_align = interp->sh_addralign;
+ }
+
+ /* if dynamic section, then add corresponding program header */
+ if (dynamic) {
+ ph = &phdr[phnum - 1];
+
+ ph->p_type = PT_DYNAMIC;
+ ph->p_offset = dynamic->sh_offset;
+ ph->p_vaddr = dynamic->sh_addr;
+ ph->p_paddr = ph->p_vaddr;
+ ph->p_filesz = dynamic->sh_size;
+ ph->p_memsz = dynamic->sh_size;
+ ph->p_flags = PF_R | PF_W;
+ ph->p_align = dynamic->sh_addralign;
+ }
+}
+
+/* Fill the dynamic section with tags describing the address and size of
+ sections */
+static void fill_dynamic(TCCState *s1, struct dyn_inf *dyninf)
+{
+ Section *dynamic;
+
+ dynamic = dyninf->dynamic;
+
+ /* put dynamic section entries */
+ dynamic->data_offset = dyninf->dyn_rel_off;
+ put_dt(dynamic, DT_HASH, s1->dynsym->hash->sh_addr);
+ put_dt(dynamic, DT_STRTAB, dyninf->dynstr->sh_addr);
+ put_dt(dynamic, DT_SYMTAB, s1->dynsym->sh_addr);
+ put_dt(dynamic, DT_STRSZ, dyninf->dynstr->data_offset);
+ put_dt(dynamic, DT_SYMENT, sizeof(ElfW(Sym)));
+#if defined(TCC_TARGET_ARM64) || defined(TCC_TARGET_X86_64)
+ put_dt(dynamic, DT_RELA, dyninf->rel_addr);
+ put_dt(dynamic, DT_RELASZ, dyninf->rel_size);
+ put_dt(dynamic, DT_RELAENT, sizeof(ElfW_Rel));
+#else
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+ put_dt(dynamic, DT_PLTGOT, s1->got->sh_addr);
+ put_dt(dynamic, DT_PLTRELSZ, dyninf->rel_size);
+ put_dt(dynamic, DT_JMPREL, dyninf->rel_addr);
+ put_dt(dynamic, DT_PLTREL, DT_REL);
+ put_dt(dynamic, DT_REL, dyninf->bss_addr);
+ put_dt(dynamic, DT_RELSZ, dyninf->bss_size);
+#else
+ put_dt(dynamic, DT_REL, dyninf->rel_addr);
+ put_dt(dynamic, DT_RELSZ, dyninf->rel_size);
+ put_dt(dynamic, DT_RELENT, sizeof(ElfW_Rel));
+#endif
+#endif
+ if (s1->do_debug)
+ put_dt(dynamic, DT_DEBUG, 0);
+ put_dt(dynamic, DT_NULL, 0);
+}
+
+/* Relocate remaining sections and symbols (that is those not related to
+ dynamic linking) */
+static int final_sections_reloc(TCCState *s1)
+{
+ int i;
+ Section *s;
+
+ relocate_syms(s1, 0);
+
+ if (s1->nb_errors != 0)
+ return -1;
+
+ /* relocate sections */
+ /* XXX: ignore sections with allocated relocations ? */
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[i];
+#ifdef TCC_TARGET_I386
+ if (s->reloc && s != s1->got && (s->sh_flags & SHF_ALLOC)) //gr
+ /* On X86 gdb 7.3 works in any case but gdb 6.6 will crash if SHF_ALLOC
+ checking is removed */
+#else
+ if (s->reloc && s != s1->got)
+ /* On X86_64 gdb 7.3 will crash if SHF_ALLOC checking is present */
+#endif
+ relocate_section(s1, s);
+ }
+
+ /* relocate relocation entries if the relocation tables are
+ allocated in the executable */
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[i];
+ if ((s->sh_flags & SHF_ALLOC) &&
+ s->sh_type == SHT_RELX) {
+ relocate_rel(s1, s);
+ }
+ }
+ return 0;
+}
+
+/* Create an ELF file on disk.
+ This function handle ELF specific layout requirements */
+static void tcc_output_elf(TCCState *s1, FILE *f, int phnum, ElfW(Phdr) *phdr,
+ int file_offset, int *sec_order)
+{
+ int i, shnum, offset, size, file_type;
+ Section *s;
+ ElfW(Ehdr) ehdr;
+ ElfW(Shdr) shdr, *sh;
+
+ file_type = s1->output_type;
+ shnum = s1->nb_sections;
+
+ memset(&ehdr, 0, sizeof(ehdr));
+
+ if (phnum > 0) {
+ ehdr.e_phentsize = sizeof(ElfW(Phdr));
+ ehdr.e_phnum = phnum;
+ ehdr.e_phoff = sizeof(ElfW(Ehdr));
+ }
+
+ /* align to 4 */
+ file_offset = (file_offset + 3) & -4;
+
+ /* fill header */
+ ehdr.e_ident[0] = ELFMAG0;
+ ehdr.e_ident[1] = ELFMAG1;
+ ehdr.e_ident[2] = ELFMAG2;
+ ehdr.e_ident[3] = ELFMAG3;
+ ehdr.e_ident[4] = ELFCLASSW;
+ ehdr.e_ident[5] = ELFDATA2LSB;
+ ehdr.e_ident[6] = EV_CURRENT;
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+ ehdr.e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
+#endif
+#ifdef TCC_TARGET_ARM
+#ifdef TCC_ARM_EABI
+ ehdr.e_ident[EI_OSABI] = 0;
+ ehdr.e_flags = EF_ARM_EABI_VER4;
+ if (file_type == TCC_OUTPUT_EXE || file_type == TCC_OUTPUT_DLL)
+ ehdr.e_flags |= EF_ARM_HASENTRY;
+ if (s1->float_abi == ARM_HARD_FLOAT)
+ ehdr.e_flags |= EF_ARM_VFP_FLOAT;
+ else
+ ehdr.e_flags |= EF_ARM_SOFT_FLOAT;
+#else
+ ehdr.e_ident[EI_OSABI] = ELFOSABI_ARM;
+#endif
+#endif
+ switch(file_type) {
+ default:
+ case TCC_OUTPUT_EXE:
+ ehdr.e_type = ET_EXEC;
+ ehdr.e_entry = get_elf_sym_addr(s1, "_start", 1);
+ break;
+ case TCC_OUTPUT_DLL:
+ ehdr.e_type = ET_DYN;
+ ehdr.e_entry = text_section->sh_addr; /* XXX: is it correct ? */
+ break;
+ case TCC_OUTPUT_OBJ:
+ ehdr.e_type = ET_REL;
+ break;
+ }
+ ehdr.e_machine = EM_TCC_TARGET;
+ ehdr.e_version = EV_CURRENT;
+ ehdr.e_shoff = file_offset;
+ ehdr.e_ehsize = sizeof(ElfW(Ehdr));
+ ehdr.e_shentsize = sizeof(ElfW(Shdr));
+ ehdr.e_shnum = shnum;
+ ehdr.e_shstrndx = shnum - 1;
+
+ fwrite(&ehdr, 1, sizeof(ElfW(Ehdr)), f);
+ fwrite(phdr, 1, phnum * sizeof(ElfW(Phdr)), f);
+ offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
+
+ sort_syms(s1, symtab_section);
+ for(i = 1; i < s1->nb_sections; i++) {
+ s = s1->sections[sec_order[i]];
+ if (s->sh_type != SHT_NOBITS) {
+ if (s->sh_type == SHT_DYNSYM)
+ patch_dynsym_undef(s1, s);
+ while (offset < s->sh_offset) {
+ fputc(0, f);
+ offset++;
+ }
+ size = s->sh_size;
+ fwrite(s->data, 1, size, f);
+ offset += size;
+ }
+ }
+
+ /* output section headers */
+ while (offset < ehdr.e_shoff) {
+ fputc(0, f);
+ offset++;
+ }
+
+ for(i = 0; i < s1->nb_sections; i++) {
+ sh = &shdr;
+ memset(sh, 0, sizeof(ElfW(Shdr)));
+ s = s1->sections[i];
+ if (s) {
+ sh->sh_name = s->sh_name;
+ sh->sh_type = s->sh_type;
+ sh->sh_flags = s->sh_flags;
+ sh->sh_entsize = s->sh_entsize;
+ sh->sh_info = s->sh_info;
+ if (s->link)
+ sh->sh_link = s->link->sh_num;
+ sh->sh_addralign = s->sh_addralign;
+ sh->sh_addr = s->sh_addr;
+ sh->sh_offset = s->sh_offset;
+ sh->sh_size = s->sh_size;
+ }
+ fwrite(sh, 1, sizeof(ElfW(Shdr)), f);
+ }
+}
+
+/* Write an elf, coff or "binary" file */
+static int tcc_write_elf_file(TCCState *s1, const char *filename, int phnum,
+ ElfW(Phdr) *phdr, int file_offset, int *sec_order)
+{
+ int fd, mode, file_type;
+ FILE *f;
+
+ file_type = s1->output_type;
+ if (file_type == TCC_OUTPUT_OBJ)
+ mode = 0666;
+ else
+ mode = 0777;
+ unlink(filename);
+ fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, mode);
+ if (fd < 0) {
+ tcc_error_noabort("could not write '%s'", filename);
+ return -1;
+ }
+ f = fdopen(fd, "wb");
+ if (s1->verbose)
+ printf("<- %s\n", filename);
+
+#ifdef TCC_TARGET_COFF
+ if (s1->output_format == TCC_OUTPUT_FORMAT_COFF)
+ tcc_output_coff(s1, f);
+ else
+#endif
+ if (s1->output_format == TCC_OUTPUT_FORMAT_ELF)
+ tcc_output_elf(s1, f, phnum, phdr, file_offset, sec_order);
+ else
+ tcc_output_binary(s1, f, sec_order);
+ fclose(f);
+
+ return 0;
+}
+
+/* Output an elf, coff or binary file */
+/* XXX: suppress unneeded sections */
+static int elf_output_file(TCCState *s1, const char *filename)
+{
+ int i, ret, phnum, shnum, file_type, file_offset, *sec_order;
+ struct dyn_inf dyninf;
+ ElfW(Phdr) *phdr;
+ ElfW(Sym) *sym;
+ Section *strsec, *interp, *dynamic, *dynstr;
+
+ file_type = s1->output_type;
+ s1->nb_errors = 0;
+
+ /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
+ if (file_type != TCC_OUTPUT_OBJ) {
+ tcc_add_runtime(s1);
+ }
+
+ phdr = NULL;
+ sec_order = NULL;
+ interp = dynamic = dynstr = NULL; /* avoid warning */
+ dyninf.dyn_rel_off = 0; /* avoid warning */
+
+ if (file_type != TCC_OUTPUT_OBJ) {
+ relocate_common_syms();
+
+ tcc_add_linker_symbols(s1);
+
+ if (!s1->static_link) {
+ if (file_type == TCC_OUTPUT_EXE) {
+ char *ptr;
+ /* allow override the dynamic loader */
+ const char *elfint = getenv("LD_SO");
+ if (elfint == NULL)
+ elfint = DEFAULT_ELFINTERP(s1);
+ /* add interpreter section only if executable */
+ interp = new_section(s1, ".interp", SHT_PROGBITS, SHF_ALLOC);
+ interp->sh_addralign = 1;
+ ptr = section_ptr_add(interp, 1 + strlen(elfint));
+ strcpy(ptr, elfint);
+ }
+
+ /* add dynamic symbol table */
+ s1->dynsym = new_symtab(s1, ".dynsym", SHT_DYNSYM, SHF_ALLOC,
+ ".dynstr",
+ ".hash", SHF_ALLOC);
+ dynstr = s1->dynsym->link;
+
+ /* add dynamic section */
+ dynamic = new_section(s1, ".dynamic", SHT_DYNAMIC,
+ SHF_ALLOC | SHF_WRITE);
+ dynamic->link = dynstr;
+ dynamic->sh_entsize = sizeof(ElfW(Dyn));
+
+ build_got(s1);
+
+ if (file_type == TCC_OUTPUT_EXE) {
+ bind_exe_dynsyms(s1);
+
+ if (s1->nb_errors) {
+ ret = -1;
+ goto the_end;
+ }
+
+ bind_libs_dynsyms(s1);
+ } else /* shared library case: simply export all global symbols */
+ export_global_syms(s1);
+
+ build_got_entries(s1);
+
+ /* add a list of needed dlls */
+ for(i = 0; i < s1->nb_loaded_dlls; i++) {
+ DLLReference *dllref = s1->loaded_dlls[i];
+ if (dllref->level == 0)
+ put_dt(dynamic, DT_NEEDED, put_elf_str(dynstr, dllref->name));
+ }
+
+ if (s1->rpath)
+ put_dt(dynamic, DT_RPATH, put_elf_str(dynstr, s1->rpath));
+
+ /* XXX: currently, since we do not handle PIC code, we
+ must relocate the readonly segments */
+ if (file_type == TCC_OUTPUT_DLL) {
+ if (s1->soname)
+ put_dt(dynamic, DT_SONAME, put_elf_str(dynstr, s1->soname));
+ put_dt(dynamic, DT_TEXTREL, 0);
+ }
+
+ if (s1->symbolic)
+ put_dt(dynamic, DT_SYMBOLIC, 0);
+
+ /* add necessary space for other entries */
+ dyninf.dyn_rel_off = dynamic->data_offset;
+ dynamic->data_offset += sizeof(ElfW(Dyn)) * EXTRA_RELITEMS;
+ } else {
+ /* still need to build got entries in case of static link */
+ build_got_entries(s1);
+ }
+ }
+
+ /* we add a section for symbols */
+ strsec = new_section(s1, ".shstrtab", SHT_STRTAB, 0);
+ put_elf_str(strsec, "");
+
+ /* compute number of sections */
+ shnum = s1->nb_sections;
+
+ /* this array is used to reorder sections in the output file */
+ sec_order = tcc_malloc(sizeof(int) * shnum);
+ sec_order[0] = 0;
+
+ /* compute number of program headers */
+ switch(file_type) {
+ default:
+ case TCC_OUTPUT_OBJ:
+ phnum = 0;
+ break;
+ case TCC_OUTPUT_EXE:
+ if (!s1->static_link)
+ phnum = 4 + HAVE_PHDR;
+ else
+ phnum = 2;
+ break;
+ case TCC_OUTPUT_DLL:
+ phnum = 3;
+ break;
+ }
+
+ /* Allocate strings for section names */
+ alloc_sec_names(s1, file_type, strsec);
+
+ /* allocate program segment headers */
+ phdr = tcc_mallocz(phnum * sizeof(ElfW(Phdr)));
+
+ /* compute section to program header mapping */
+ file_offset = layout_sections(s1, phdr, phnum, interp, strsec, &dyninf,
+ sec_order);
+
+ /* Fill remaining program header and finalize relocation related to dynamic
+ linking. */
+ if (phnum > 0) {
+ fill_unloadable_phdr(phdr, phnum, interp, dynamic);
+ if (dynamic) {
+ dyninf.dynamic = dynamic;
+ dyninf.dynstr = dynstr;
+
+ fill_dynamic(s1, &dyninf);
+
+ /* put in GOT the dynamic section address and relocate PLT */
+ put32(s1->got->data, dynamic->sh_addr);
+ if (file_type == TCC_OUTPUT_EXE
+#if defined(TCC_OUTPUT_DLL_WITH_PLT)
+ || file_type == TCC_OUTPUT_DLL
+#endif
+ )
+ relocate_plt(s1);
+
+ /* relocate symbols in .dynsym now that final addresses are known */
+ for_each_elem(s1->dynsym, 1, sym, ElfW(Sym)) {
+ if (sym->st_shndx == SHN_UNDEF) {
+ /* relocate to PLT if symbol corresponds to a PLT entry,
+ but not if it's a weak symbol */
+ if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK)
+ sym->st_value = 0;
+ else if (sym->st_value)
+ sym->st_value += s1->plt->sh_addr;
+ } else if (sym->st_shndx < SHN_LORESERVE) {
+ /* do symbol relocation */
+ sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
+ }
+ }
+ }
+ }
+
+ /* if building executable or DLL, then relocate each section
+ except the GOT which is already relocated */
+ if (file_type != TCC_OUTPUT_OBJ) {
+ ret = final_sections_reloc(s1);
+ if (ret)
+ goto the_end;
+ }
+
+ /* Perform relocation to GOT or PLT entries */
+ if (file_type == TCC_OUTPUT_EXE && s1->static_link)
+ fill_got(s1);
+
+ /* Create the ELF file with name 'filename' */
+ ret = tcc_write_elf_file(s1, filename, phnum, phdr, file_offset, sec_order);
+ if (s1->do_strip) {
+ int rc;
+ const char *strip_cmd = "sstrip "; // super strip utility from ELFkickers
+ const char *null_dev = " 2> /dev/null";
+ char buf[1050];
+ snprintf(buf, sizeof(buf), "%s%s%s", strip_cmd, filename, null_dev);
+ rc = system(buf);
+ if (rc)
+ system(buf+1); // call a strip utility from binutils
+ }
+ the_end:
+ tcc_free(s1->symtab_to_dynsym);
+ tcc_free(sec_order);
+ tcc_free(phdr);
+ tcc_free(s1->sym_attrs);
+ s1->sym_attrs = NULL;
+ return ret;
+}
+
+LIBTCCAPI int tcc_output_file(TCCState *s, const char *filename)
+{
+ int ret;
+#ifdef TCC_TARGET_PE
+ if (s->output_type != TCC_OUTPUT_OBJ) {
+ ret = pe_output_file(s, filename);
+ } else
+#endif
+ ret = elf_output_file(s, filename);
+ return ret;
+}
+
+static void *load_data(int fd, unsigned long file_offset, unsigned long size)
+{
+ void *data;
+
+ data = tcc_malloc(size);
+ lseek(fd, file_offset, SEEK_SET);
+ read(fd, data, size);
+ return data;
+}
+
+typedef struct SectionMergeInfo {
+ Section *s; /* corresponding existing section */
+ unsigned long offset; /* offset of the new section in the existing section */
+ uint8_t new_section; /* true if section 's' was added */
+ uint8_t link_once; /* true if link once section */
+} SectionMergeInfo;
+
+/* load an object file and merge it with current files */
+/* XXX: handle correctly stab (debug) info */
+ST_FUNC int tcc_load_object_file(TCCState *s1,
+ int fd, unsigned long file_offset)
+{
+ ElfW(Ehdr) ehdr;
+ ElfW(Shdr) *shdr, *sh;
+ int size, i, j, offset, offseti, nb_syms, sym_index, ret;
+ unsigned char *strsec, *strtab;
+ int *old_to_new_syms;
+ char *sh_name, *name;
+ SectionMergeInfo *sm_table, *sm;
+ ElfW(Sym) *sym, *symtab;
+ ElfW_Rel *rel;
+ Section *s;
+
+ int stab_index;
+ int stabstr_index;
+
+ stab_index = stabstr_index = 0;
+
+ if (read(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
+ goto fail1;
+ if (ehdr.e_ident[0] != ELFMAG0 ||
+ ehdr.e_ident[1] != ELFMAG1 ||
+ ehdr.e_ident[2] != ELFMAG2 ||
+ ehdr.e_ident[3] != ELFMAG3)
+ goto fail1;
+ /* test if object file */
+ if (ehdr.e_type != ET_REL)
+ goto fail1;
+ /* test CPU specific stuff */
+ if (ehdr.e_ident[5] != ELFDATA2LSB ||
+ ehdr.e_machine != EM_TCC_TARGET) {
+ fail1:
+ tcc_error_noabort("invalid object file");
+ return -1;
+ }
+ /* read sections */
+ shdr = load_data(fd, file_offset + ehdr.e_shoff,
+ sizeof(ElfW(Shdr)) * ehdr.e_shnum);
+ sm_table = tcc_mallocz(sizeof(SectionMergeInfo) * ehdr.e_shnum);
+
+ /* load section names */
+ sh = &shdr[ehdr.e_shstrndx];
+ strsec = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
+
+ /* load symtab and strtab */
+ old_to_new_syms = NULL;
+ symtab = NULL;
+ strtab = NULL;
+ nb_syms = 0;
+ for(i = 1; i < ehdr.e_shnum; i++) {
+ sh = &shdr[i];
+ if (sh->sh_type == SHT_SYMTAB) {
+ if (symtab) {
+ tcc_error_noabort("object must contain only one symtab");
+ fail:
+ ret = -1;
+ goto the_end;
+ }
+ nb_syms = sh->sh_size / sizeof(ElfW(Sym));
+ symtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
+ sm_table[i].s = symtab_section;
+
+ /* now load strtab */
+ sh = &shdr[sh->sh_link];
+ strtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
+ }
+ }
+
+ /* now examine each section and try to merge its content with the
+ ones in memory */
+ for(i = 1; i < ehdr.e_shnum; i++) {
+ /* no need to examine section name strtab */
+ if (i == ehdr.e_shstrndx)
+ continue;
+ sh = &shdr[i];
+ sh_name = (char *) strsec + sh->sh_name;
+ /* ignore sections types we do not handle */
+ if (sh->sh_type != SHT_PROGBITS &&
+ sh->sh_type != SHT_RELX &&
+#ifdef TCC_ARM_EABI
+ sh->sh_type != SHT_ARM_EXIDX &&
+#endif
+ sh->sh_type != SHT_NOBITS &&
+ sh->sh_type != SHT_PREINIT_ARRAY &&
+ sh->sh_type != SHT_INIT_ARRAY &&
+ sh->sh_type != SHT_FINI_ARRAY &&
+ strcmp(sh_name, ".stabstr")
+ )
+ continue;
+ if (sh->sh_addralign < 1)
+ sh->sh_addralign = 1;
+ /* find corresponding section, if any */
+ for(j = 1; j < s1->nb_sections;j++) {
+ s = s1->sections[j];
+ if (!strcmp(s->name, sh_name)) {
+ if (!strncmp(sh_name, ".gnu.linkonce",
+ sizeof(".gnu.linkonce") - 1)) {
+ /* if a 'linkonce' section is already present, we
+ do not add it again. It is a little tricky as
+ symbols can still be defined in
+ it. */
+ sm_table[i].link_once = 1;
+ goto next;
+ } else {
+ goto found;
+ }
+ }
+ }
+ /* not found: create new section */
+ s = new_section(s1, sh_name, sh->sh_type, sh->sh_flags);
+ /* take as much info as possible from the section. sh_link and
+ sh_info will be updated later */
+ s->sh_addralign = sh->sh_addralign;
+ s->sh_entsize = sh->sh_entsize;
+ sm_table[i].new_section = 1;
+ found:
+ if (sh->sh_type != s->sh_type) {
+ tcc_error_noabort("invalid section type");
+ goto fail;
+ }
+
+ /* align start of section */
+ offset = s->data_offset;
+
+ if (0 == strcmp(sh_name, ".stab")) {
+ stab_index = i;
+ goto no_align;
+ }
+ if (0 == strcmp(sh_name, ".stabstr")) {
+ stabstr_index = i;
+ goto no_align;
+ }
+
+ size = sh->sh_addralign - 1;
+ offset = (offset + size) & ~size;
+ if (sh->sh_addralign > s->sh_addralign)
+ s->sh_addralign = sh->sh_addralign;
+ s->data_offset = offset;
+ no_align:
+ sm_table[i].offset = offset;
+ sm_table[i].s = s;
+ /* concatenate sections */
+ size = sh->sh_size;
+ if (sh->sh_type != SHT_NOBITS) {
+ unsigned char *ptr;
+ lseek(fd, file_offset + sh->sh_offset, SEEK_SET);
+ ptr = section_ptr_add(s, size);
+ read(fd, ptr, size);
+ } else {
+ s->data_offset += size;
+ }
+ next: ;
+ }
+
+ /* gr relocate stab strings */
+ if (stab_index && stabstr_index) {
+ Stab_Sym *a, *b;
+ unsigned o;
+ s = sm_table[stab_index].s;
+ a = (Stab_Sym *)(s->data + sm_table[stab_index].offset);
+ b = (Stab_Sym *)(s->data + s->data_offset);
+ o = sm_table[stabstr_index].offset;
+ while (a < b)
+ a->n_strx += o, a++;
+ }
+
+ /* second short pass to update sh_link and sh_info fields of new
+ sections */
+ for(i = 1; i < ehdr.e_shnum; i++) {
+ s = sm_table[i].s;
+ if (!s || !sm_table[i].new_section)
+ continue;
+ sh = &shdr[i];
+ if (sh->sh_link > 0)
+ s->link = sm_table[sh->sh_link].s;
+ if (sh->sh_type == SHT_RELX) {
+ s->sh_info = sm_table[sh->sh_info].s->sh_num;
+ /* update backward link */
+ s1->sections[s->sh_info]->reloc = s;
+ }
+ }
+ sm = sm_table;
+
+ /* resolve symbols */
+ old_to_new_syms = tcc_mallocz(nb_syms * sizeof(int));
+
+ sym = symtab + 1;
+ for(i = 1; i < nb_syms; i++, sym++) {
+ if (sym->st_shndx != SHN_UNDEF &&
+ sym->st_shndx < SHN_LORESERVE) {
+ sm = &sm_table[sym->st_shndx];
+ if (sm->link_once) {
+ /* if a symbol is in a link once section, we use the
+ already defined symbol. It is very important to get
+ correct relocations */
+ if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
+ name = (char *) strtab + sym->st_name;
+ sym_index = find_elf_sym(symtab_section, name);
+ if (sym_index)
+ old_to_new_syms[i] = sym_index;
+ }
+ continue;
+ }
+ /* if no corresponding section added, no need to add symbol */
+ if (!sm->s)
+ continue;
+ /* convert section number */
+ sym->st_shndx = sm->s->sh_num;
+ /* offset value */
+ sym->st_value += sm->offset;
+ }
+ /* add symbol */
+ name = (char *) strtab + sym->st_name;
+ sym_index = add_elf_sym(symtab_section, sym->st_value, sym->st_size,
+ sym->st_info, sym->st_other,
+ sym->st_shndx, name);
+ old_to_new_syms[i] = sym_index;
+ }
+
+ /* third pass to patch relocation entries */
+ for(i = 1; i < ehdr.e_shnum; i++) {
+ s = sm_table[i].s;
+ if (!s)
+ continue;
+ sh = &shdr[i];
+ offset = sm_table[i].offset;
+ switch(s->sh_type) {
+ case SHT_RELX:
+ /* take relocation offset information */
+ offseti = sm_table[sh->sh_info].offset;
+ for_each_elem(s, (offset / sizeof(*rel)), rel, ElfW_Rel) {
+ int type;
+ unsigned sym_index;
+ /* convert symbol index */
+ type = ELFW(R_TYPE)(rel->r_info);
+ sym_index = ELFW(R_SYM)(rel->r_info);
+ /* NOTE: only one symtab assumed */
+ if (sym_index >= nb_syms)
+ goto invalid_reloc;
+ sym_index = old_to_new_syms[sym_index];
+ /* ignore link_once in rel section. */
+ if (!sym_index && !sm->link_once
+#ifdef TCC_TARGET_ARM
+ && type != R_ARM_V4BX
+#endif
+ ) {
+ invalid_reloc:
+ tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
+ i, strsec + sh->sh_name, rel->r_offset);
+ goto fail;
+ }
+ rel->r_info = ELFW(R_INFO)(sym_index, type);
+ /* offset the relocation offset */
+ rel->r_offset += offseti;
+#ifdef TCC_TARGET_ARM
+ /* Jumps and branches from a Thumb code to a PLT entry need
+ special handling since PLT entries are ARM code.
+ Unconditional bl instructions referencing PLT entries are
+ handled by converting these instructions into blx
+ instructions. Other case of instructions referencing a PLT
+ entry require to add a Thumb stub before the PLT entry to
+ switch to ARM mode. We set bit plt_thumb_stub of the
+ attribute of a symbol to indicate such a case. */
+ if (type == R_ARM_THM_JUMP24)
+ alloc_sym_attr(s1, sym_index)->plt_thumb_stub = 1;
+#endif
+ }
+ break;
+ default:
+ break;
+ }
+ }
+
+ ret = 0;
+ the_end:
+ tcc_free(symtab);
+ tcc_free(strtab);
+ tcc_free(old_to_new_syms);
+ tcc_free(sm_table);
+ tcc_free(strsec);
+ tcc_free(shdr);
+ return ret;
+}
+
+typedef struct ArchiveHeader {
+ char ar_name[16]; /* name of this member */
+ char ar_date[12]; /* file mtime */
+ char ar_uid[6]; /* owner uid; printed as decimal */
+ char ar_gid[6]; /* owner gid; printed as decimal */
+ char ar_mode[8]; /* file mode, printed as octal */
+ char ar_size[10]; /* file size, printed as decimal */
+ char ar_fmag[2]; /* should contain ARFMAG */
+} ArchiveHeader;
+
+static int get_be32(const uint8_t *b)
+{
+ return b[3] | (b[2] << 8) | (b[1] << 16) | (b[0] << 24);
+}
+
+/* load only the objects which resolve undefined symbols */
+static int tcc_load_alacarte(TCCState *s1, int fd, int size)
+{
+ int i, bound, nsyms, sym_index, off, ret;
+ uint8_t *data;
+ const char *ar_names, *p;
+ const uint8_t *ar_index;
+ ElfW(Sym) *sym;
+
+ data = tcc_malloc(size);
+ if (read(fd, data, size) != size)
+ goto fail;
+ nsyms = get_be32(data);
+ ar_index = data + 4;
+ ar_names = (char *) ar_index + nsyms * 4;
+
+ do {
+ bound = 0;
+ for(p = ar_names, i = 0; i < nsyms; i++, p += strlen(p)+1) {
+ sym_index = find_elf_sym(symtab_section, p);
+ if(sym_index) {
+ sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+ if(sym->st_shndx == SHN_UNDEF) {
+ off = get_be32(ar_index + i * 4) + sizeof(ArchiveHeader);
+ ++bound;
+ lseek(fd, off, SEEK_SET);
+ if(tcc_load_object_file(s1, fd, off) < 0) {
+ fail:
+ ret = -1;
+ goto the_end;
+ }
+ }
+ }
+ }
+ } while(bound);
+ ret = 0;
+ the_end:
+ tcc_free(data);
+ return ret;
+}
+
+/* load a '.a' file */
+ST_FUNC int tcc_load_archive(TCCState *s1, int fd)
+{
+ ArchiveHeader hdr;
+ char ar_size[11];
+ char ar_name[17];
+ char magic[8];
+ int size, len, i;
+ unsigned long file_offset;
+
+ /* skip magic which was already checked */
+ read(fd, magic, sizeof(magic));
+
+ for(;;) {
+ len = read(fd, &hdr, sizeof(hdr));
+ if (len == 0)
+ break;
+ if (len != sizeof(hdr)) {
+ tcc_error_noabort("invalid archive");
+ return -1;
+ }
+ memcpy(ar_size, hdr.ar_size, sizeof(hdr.ar_size));
+ ar_size[sizeof(hdr.ar_size)] = '\0';
+ size = strtol(ar_size, NULL, 0);
+ memcpy(ar_name, hdr.ar_name, sizeof(hdr.ar_name));
+ for(i = sizeof(hdr.ar_name) - 1; i >= 0; i--) {
+ if (ar_name[i] != ' ')
+ break;
+ }
+ ar_name[i + 1] = '\0';
+ file_offset = lseek(fd, 0, SEEK_CUR);
+ /* align to even */
+ size = (size + 1) & ~1;
+ if (!strcmp(ar_name, "/")) {
+ /* coff symbol table : we handle it */
+ if(s1->alacarte_link)
+ return tcc_load_alacarte(s1, fd, size);
+ } else if (!strcmp(ar_name, "//") ||
+ !strcmp(ar_name, "__.SYMDEF") ||
+ !strcmp(ar_name, "__.SYMDEF/") ||
+ !strcmp(ar_name, "ARFILENAMES/")) {
+ /* skip symbol table or archive names */
+ } else {
+ if (tcc_load_object_file(s1, fd, file_offset) < 0)
+ return -1;
+ }
+ lseek(fd, file_offset + size, SEEK_SET);
+ }
+ return 0;
+}
+
+#ifndef TCC_TARGET_PE
+/* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
+ is referenced by the user (so it should be added as DT_NEEDED in
+ the generated ELF file) */
+ST_FUNC int tcc_load_dll(TCCState *s1, int fd, const char *filename, int level)
+{
+ ElfW(Ehdr) ehdr;
+ ElfW(Shdr) *shdr, *sh, *sh1;
+ int i, j, nb_syms, nb_dts, sym_bind, ret;
+ ElfW(Sym) *sym, *dynsym;
+ ElfW(Dyn) *dt, *dynamic;
+ unsigned char *dynstr;
+ const char *name, *soname;
+ DLLReference *dllref;
+
+ read(fd, &ehdr, sizeof(ehdr));
+
+ /* test CPU specific stuff */
+ if (ehdr.e_ident[5] != ELFDATA2LSB ||
+ ehdr.e_machine != EM_TCC_TARGET) {
+ tcc_error_noabort("bad architecture");
+ return -1;
+ }
+
+ /* read sections */
+ shdr = load_data(fd, ehdr.e_shoff, sizeof(ElfW(Shdr)) * ehdr.e_shnum);
+
+ /* load dynamic section and dynamic symbols */
+ nb_syms = 0;
+ nb_dts = 0;
+ dynamic = NULL;
+ dynsym = NULL; /* avoid warning */
+ dynstr = NULL; /* avoid warning */
+ for(i = 0, sh = shdr; i < ehdr.e_shnum; i++, sh++) {
+ switch(sh->sh_type) {
+ case SHT_DYNAMIC:
+ nb_dts = sh->sh_size / sizeof(ElfW(Dyn));
+ dynamic = load_data(fd, sh->sh_offset, sh->sh_size);
+ break;
+ case SHT_DYNSYM:
+ nb_syms = sh->sh_size / sizeof(ElfW(Sym));
+ dynsym = load_data(fd, sh->sh_offset, sh->sh_size);
+ sh1 = &shdr[sh->sh_link];
+ dynstr = load_data(fd, sh1->sh_offset, sh1->sh_size);
+ break;
+ default:
+ break;
+ }
+ }
+
+ /* compute the real library name */
+ soname = tcc_basename(filename);
+
+ for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
+ if (dt->d_tag == DT_SONAME) {
+ soname = (char *) dynstr + dt->d_un.d_val;
+ }
+ }
+
+ /* if the dll is already loaded, do not load it */
+ for(i = 0; i < s1->nb_loaded_dlls; i++) {
+ dllref = s1->loaded_dlls[i];
+ if (!strcmp(soname, dllref->name)) {
+ /* but update level if needed */
+ if (level < dllref->level)
+ dllref->level = level;
+ ret = 0;
+ goto the_end;
+ }
+ }
+
+ /* add the dll and its level */
+ dllref = tcc_mallocz(sizeof(DLLReference) + strlen(soname));
+ dllref->level = level;
+ strcpy(dllref->name, soname);
+ dynarray_add((void ***)&s1->loaded_dlls, &s1->nb_loaded_dlls, dllref);
+
+ /* add dynamic symbols in dynsym_section */
+ for(i = 1, sym = dynsym + 1; i < nb_syms; i++, sym++) {
+ sym_bind = ELFW(ST_BIND)(sym->st_info);
+ if (sym_bind == STB_LOCAL)
+ continue;
+ name = (char *) dynstr + sym->st_name;
+ add_elf_sym(s1->dynsymtab_section, sym->st_value, sym->st_size,
+ sym->st_info, sym->st_other, sym->st_shndx, name);
+ }
+
+ /* load all referenced DLLs */
+ for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
+ switch(dt->d_tag) {
+ case DT_NEEDED:
+ name = (char *) dynstr + dt->d_un.d_val;
+ for(j = 0; j < s1->nb_loaded_dlls; j++) {
+ dllref = s1->loaded_dlls[j];
+ if (!strcmp(name, dllref->name))
+ goto already_loaded;
+ }
+ if (tcc_add_dll(s1, name, AFF_REFERENCED_DLL) < 0) {
+ tcc_error_noabort("referenced dll '%s' not found", name);
+ ret = -1;
+ goto the_end;
+ }
+ already_loaded:
+ break;
+ }
+ }
+ ret = 0;
+ the_end:
+ tcc_free(dynstr);
+ tcc_free(dynsym);
+ tcc_free(dynamic);
+ tcc_free(shdr);
+ return ret;
+}
+
+#define LD_TOK_NAME 256
+#define LD_TOK_EOF (-1)
+
+/* return next ld script token */
+static int ld_next(TCCState *s1, char *name, int name_size)
+{
+ int c;
+ char *q;
+
+ redo:
+ switch(ch) {
+ case ' ':
+ case '\t':
+ case '\f':
+ case '\v':
+ case '\r':
+ case '\n':
+ inp();
+ goto redo;
+ case '/':
+ minp();
+ if (ch == '*') {
+ file->buf_ptr = parse_comment(file->buf_ptr);
+ ch = file->buf_ptr[0];
+ goto redo;
+ } else {
+ q = name;
+ *q++ = '/';
+ goto parse_name;
+ }
+ break;
+ case '\\':
+ ch = handle_eob();
+ if (ch != '\\')
+ goto redo;
+ /* fall through */
+ /* case 'a' ... 'z': */
+ case 'a':
+ case 'b':
+ case 'c':
+ case 'd':
+ case 'e':
+ case 'f':
+ case 'g':
+ case 'h':
+ case 'i':
+ case 'j':
+ case 'k':
+ case 'l':
+ case 'm':
+ case 'n':
+ case 'o':
+ case 'p':
+ case 'q':
+ case 'r':
+ case 's':
+ case 't':
+ case 'u':
+ case 'v':
+ case 'w':
+ case 'x':
+ case 'y':
+ case 'z':
+ /* case 'A' ... 'z': */
+ case 'A':
+ case 'B':
+ case 'C':
+ case 'D':
+ case 'E':
+ case 'F':
+ case 'G':
+ case 'H':
+ case 'I':
+ case 'J':
+ case 'K':
+ case 'L':
+ case 'M':
+ case 'N':
+ case 'O':
+ case 'P':
+ case 'Q':
+ case 'R':
+ case 'S':
+ case 'T':
+ case 'U':
+ case 'V':
+ case 'W':
+ case 'X':
+ case 'Y':
+ case 'Z':
+ case '_':
+ case '.':
+ case '$':
+ case '~':
+ q = name;
+ parse_name:
+ for(;;) {
+ if (!((ch >= 'a' && ch <= 'z') ||
+ (ch >= 'A' && ch <= 'Z') ||
+ (ch >= '0' && ch <= '9') ||
+ strchr("/.-_+=$:\\,~", ch)))
+ break;
+ if ((q - name) < name_size - 1) {
+ *q++ = ch;
+ }
+ minp();
+ }
+ *q = '\0';
+ c = LD_TOK_NAME;
+ break;
+ case CH_EOF:
+ c = LD_TOK_EOF;
+ break;
+ default:
+ c = ch;
+ inp();
+ break;
+ }
+ return c;
+}
+
+static int ld_add_file(TCCState *s1, const char filename[])
+{
+ int ret;
+
+ ret = tcc_add_file_internal(s1, filename, 0, TCC_FILETYPE_BINARY);
+ if (ret)
+ ret = tcc_add_dll(s1, filename, 0);
+ return ret;
+}
+
+static inline int new_undef_syms(void)
+{
+ int ret = 0;
+ ret = new_undef_sym;
+ new_undef_sym = 0;
+ return ret;
+}
+
+static int ld_add_file_list(TCCState *s1, const char *cmd, int as_needed)
+{
+ char filename[1024], libname[1024];
+ int t, group, nblibs = 0, ret = 0;
+ char **libs = NULL;
+
+ group = !strcmp(cmd, "GROUP");
+ if (!as_needed)
+ new_undef_syms();
+ t = ld_next(s1, filename, sizeof(filename));
+ if (t != '(')
+ expect("(");
+ t = ld_next(s1, filename, sizeof(filename));
+ for(;;) {
+ libname[0] = '\0';
+ if (t == LD_TOK_EOF) {
+ tcc_error_noabort("unexpected end of file");
+ ret = -1;
+ goto lib_parse_error;
+ } else if (t == ')') {
+ break;
+ } else if (t == '-') {
+ t = ld_next(s1, filename, sizeof(filename));
+ if ((t != LD_TOK_NAME) || (filename[0] != 'l')) {
+ tcc_error_noabort("library name expected");
+ ret = -1;
+ goto lib_parse_error;
+ }
+ pstrcpy(libname, sizeof libname, &filename[1]);
+ if (s1->static_link) {
+ snprintf(filename, sizeof filename, "lib%s.a", libname);
+ } else {
+ snprintf(filename, sizeof filename, "lib%s.so", libname);
+ }
+ } else if (t != LD_TOK_NAME) {
+ tcc_error_noabort("filename expected");
+ ret = -1;
+ goto lib_parse_error;
+ }
+ if (!strcmp(filename, "AS_NEEDED")) {
+ ret = ld_add_file_list(s1, cmd, 1);
+ if (ret)
+ goto lib_parse_error;
+ } else {
+ /* TODO: Implement AS_NEEDED support. Ignore it for now */
+ if (!as_needed) {
+ ret = ld_add_file(s1, filename);
+ if (ret)
+ goto lib_parse_error;
+ if (group) {
+ /* Add the filename *and* the libname to avoid future conversions */
+ dynarray_add((void ***) &libs, &nblibs, tcc_strdup(filename));
+ if (libname[0] != '\0')
+ dynarray_add((void ***) &libs, &nblibs, tcc_strdup(libname));
+ }
+ }
+ }
+ t = ld_next(s1, filename, sizeof(filename));
+ if (t == ',') {
+ t = ld_next(s1, filename, sizeof(filename));
+ }
+ }
+ if (group && !as_needed) {
+ while (new_undef_syms()) {
+ int i;
+
+ for (i = 0; i < nblibs; i ++)
+ ld_add_file(s1, libs[i]);
+ }
+ }
+lib_parse_error:
+ dynarray_reset(&libs, &nblibs);
+ return ret;
+}
+
+/* interpret a subset of GNU ldscripts to handle the dummy libc.so
+ files */
+ST_FUNC int tcc_load_ldscript(TCCState *s1)
+{
+ char cmd[64];
+ char filename[1024];
+ int t, ret;
+
+ ch = handle_eob();
+ for(;;) {
+ t = ld_next(s1, cmd, sizeof(cmd));
+ if (t == LD_TOK_EOF)
+ return 0;
+ else if (t != LD_TOK_NAME)
+ return -1;
+ if (!strcmp(cmd, "INPUT") ||
+ !strcmp(cmd, "GROUP")) {
+ ret = ld_add_file_list(s1, cmd, 0);
+ if (ret)
+ return ret;
+ } else if (!strcmp(cmd, "OUTPUT_FORMAT") ||
+ !strcmp(cmd, "TARGET")) {
+ /* ignore some commands */
+ t = ld_next(s1, cmd, sizeof(cmd));
+ if (t != '(')
+ expect("(");
+ for(;;) {
+ t = ld_next(s1, filename, sizeof(filename));
+ if (t == LD_TOK_EOF) {
+ tcc_error_noabort("unexpected end of file");
+ return -1;
+ } else if (t == ')') {
+ break;
+ }
+ }
+ } else {
+ return -1;
+ }
+ }
+ return 0;
+}
+#endif /* !TCC_TARGET_PE */