diff options
Diffstat (limited to 'libasm/disasm_cb.c')
| -rw-r--r-- | libasm/disasm_cb.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/libasm/disasm_cb.c b/libasm/disasm_cb.c new file mode 100644 index 00000000..eb3689c7 --- /dev/null +++ b/libasm/disasm_cb.c @@ -0,0 +1,179 @@ +/* Copyright (C) 2005, 2007, 2008 Red Hat, Inc. + This file is part of elfutils. + Written by Ulrich Drepper <drepper@redhat.com>, 2005. + + This file is free software; you can redistribute it and/or modify + it under the terms of either + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at + your option) any later version + + or + + * the GNU General Public License as published by the Free + Software Foundation; either version 2 of the License, or (at + your option) any later version + + or both in parallel, as here. + + elfutils 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 + General Public License for more details. + + You should have received copies of the GNU General Public License and + the GNU Lesser General Public License along with this program. If + not, see <http://www.gnu.org/licenses/>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include <string.h> + +#include "libasmP.h" +#include "../libebl/libeblP.h" + + +struct symtoken +{ + DisasmCtx_t *ctx; + void *symcbarg; +}; + + +static int +default_elf_getsym (GElf_Addr addr, Elf32_Word scnndx, GElf_Addr value, + char **buf, size_t *buflen, void *arg) +{ + struct symtoken *symtoken = (struct symtoken *) arg; + + /* First try the user provided function. */ + if (symtoken->ctx->symcb != NULL) + { + int res = symtoken->ctx->symcb (addr, scnndx, value, buf, buflen, + symtoken->symcbarg); + if (res >= 0) + return res; + } + + // XXX Look up in ELF file. + + return -1; +} + + +struct symaddrpair +{ + GElf_Addr addr; + const char *name; +}; + + +static void +read_symtab_exec (DisasmCtx_t *ctx) +{ + /* We simply use all we can get our hands on. This will produce + some duplicate information but this is no problem, we simply + ignore the latter definitions. */ + Elf_Scn *scn= NULL; + while ((scn = elf_nextscn (ctx->elf, scn)) != NULL) + { + GElf_Shdr shdr_mem; + GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem); + Elf_Data *data; + if (shdr == NULL || shdr->sh_type != SHT_SYMTAB + || (data = elf_getdata (scn, NULL)) == NULL) + continue; + + int xndxscnidx = elf_scnshndx (scn); + Elf_Data *xndxdata = NULL; + if (xndxscnidx > 0) + xndxdata = elf_getdata (elf_getscn (ctx->elf, xndxscnidx), NULL); + + /* Iterate over all symbols. Add all defined symbols. */ + int nsyms = shdr->sh_size / shdr->sh_entsize; + for (int cnt = 1; cnt < nsyms; ++cnt) + { + Elf32_Word xshndx; + GElf_Sym sym_mem; + GElf_Sym *sym = gelf_getsymshndx (data, xndxdata, cnt, &sym_mem, + &xshndx); + if (sym == NULL) + continue; + + /* Undefined symbols are useless here. */ + if (sym->st_shndx == SHN_UNDEF) + continue; + + + } + } +} + + +static void +read_symtab (DisasmCtx_t *ctx) +{ + /* Find the symbol table(s). */ + GElf_Ehdr ehdr_mem; + GElf_Ehdr *ehdr = gelf_getehdr (ctx->elf, &ehdr_mem); + if (ehdr == NULL) + return; + + switch (ehdr->e_type) + { + case ET_EXEC: + case ET_DYN: + read_symtab_exec (ctx); + break; + + case ET_REL: + // XXX Handle + break; + + default: + break; + } +} + + +static int +null_elf_getsym (GElf_Addr addr __attribute__ ((unused)), + Elf32_Word scnndx __attribute__ ((unused)), + GElf_Addr value __attribute__ ((unused)), + char **buf __attribute__ ((unused)), + size_t *buflen __attribute__ ((unused)), + void *arg __attribute__ ((unused))) +{ + return -1; +} + + +int +disasm_cb (DisasmCtx_t *ctx, const uint8_t **startp, const uint8_t *end, + GElf_Addr addr, const char *fmt, DisasmOutputCB_t outcb, + void *outcbarg, void *symcbarg) +{ + struct symtoken symtoken; + DisasmGetSymCB_t getsym = ctx->symcb ?: null_elf_getsym; + + if (ctx->elf != NULL) + { + /* Read all symbols of the ELF file and stuff them into a hash + table. The key is the address and the section index. */ + read_symtab (ctx); + + symtoken.ctx = ctx; + symtoken.symcbarg = symcbarg; + + symcbarg = &symtoken; + + getsym = default_elf_getsym; + } + + return ctx->ebl->disasm (startp, end, addr, fmt, outcb, getsym, outcbarg, + symcbarg); +} +INTDEF (disasm_cb) |