1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/tools/jprof/elf.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,133 @@
1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.6 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.7 +
1.8 +#include "leaky.h"
1.9 +
1.10 +#ifdef USE_ELF
1.11 +
1.12 +#include "leaky.h"
1.13 +#include <stdio.h>
1.14 +#include <malloc.h>
1.15 +#include <libelf/libelf.h>
1.16 +#include <unistd.h>
1.17 +#include <fcntl.h>
1.18 +#include <string.h>
1.19 +
1.20 +void leaky::readSymbols(const char *fileName)
1.21 +{
1.22 + int fd = ::open(fileName, O_RDONLY);
1.23 + if (fd < 0) {
1.24 + fprintf(stderr, "%s: unable to open \"%s\"\n", applicationName,
1.25 + fileName);
1.26 + exit(-1);
1.27 + }
1.28 +
1.29 + elf_version(EV_CURRENT);
1.30 + Elf *elf = elf_begin(fd, ELF_C_READ, 0);
1.31 + if (!elf) {
1.32 + fprintf(stderr, "%s: \"%s\": has no symbol table\n", applicationName,
1.33 + fileName);
1.34 + exit(-1);
1.35 + }
1.36 +
1.37 + long alloced = 10000;
1.38 + Symbol* syms = (Symbol*) malloc(sizeof(Symbol) * 10000);
1.39 + Symbol* sp = syms;
1.40 + Symbol* last = syms + alloced;
1.41 +
1.42 + // Get each of the relevant sections and add them to the list of
1.43 + // symbols.
1.44 + Elf32_Ehdr *ehdr = elf32_getehdr(elf);
1.45 + if (!ehdr) {
1.46 + fprintf(stderr, "%s: elf library lossage\n", applicationName);
1.47 + exit(-1);
1.48 + }
1.49 +#if 0
1.50 + Elf32_Half ndx = ehdr->e_shstrndx;
1.51 +#endif
1.52 +
1.53 + Elf_Scn *scn = 0;
1.54 + int strtabndx = -1;
1.55 + for (int i = 1; (scn = elf_nextscn(elf, scn)) != 0; i++) {
1.56 + Elf32_Shdr *shdr = elf32_getshdr(scn);
1.57 +#if 0
1.58 + char *name = elf_strptr(elf, ndx, (size_t) shdr->sh_name);
1.59 + printf("Section %s (%d 0x%x)\n", name ? name : "(null)",
1.60 + shdr->sh_type, shdr->sh_type);
1.61 +#endif
1.62 + if (shdr->sh_type == SHT_STRTAB) {
1.63 + /* We assume here that string tables preceed symbol tables... */
1.64 + strtabndx = i;
1.65 + continue;
1.66 + }
1.67 +#if 0
1.68 + if (shdr->sh_type == SHT_DYNAMIC) {
1.69 + /* Dynamic */
1.70 + Elf_Data *data = elf_getdata(scn, 0);
1.71 + if (!data || !data->d_size) {
1.72 + printf("No data...");
1.73 + continue;
1.74 + }
1.75 +
1.76 + Elf32_Dyn *dyn = (Elf32_Dyn*) data->d_buf;
1.77 + Elf32_Dyn *lastdyn =
1.78 + (Elf32_Dyn*) ((char*) data->d_buf + data->d_size);
1.79 + for (; dyn < lastdyn; dyn++) {
1.80 + printf("tag=%d value=0x%x\n", dyn->d_tag, dyn->d_un.d_val);
1.81 + }
1.82 + } else
1.83 +#endif
1.84 + if ((shdr->sh_type == SHT_SYMTAB) ||
1.85 + (shdr->sh_type == SHT_DYNSYM)) {
1.86 + /* Symbol table */
1.87 + Elf_Data *data = elf_getdata(scn, 0);
1.88 + if (!data || !data->d_size) {
1.89 + printf("No data...");
1.90 + continue;
1.91 + }
1.92 +
1.93 + /* In theory we now have the symbols... */
1.94 + Elf32_Sym *esym = (Elf32_Sym*) data->d_buf;
1.95 + Elf32_Sym *lastsym =
1.96 + (Elf32_Sym*) ((char*) data->d_buf + data->d_size);
1.97 + for (; esym < lastsym; esym++) {
1.98 +#if 0
1.99 + char *nm = elf_strptr(elf, strtabndx, (size_t)esym->st_name);
1.100 + printf("%20s 0x%08x %02x %02x\n",
1.101 + nm, esym->st_value, ELF32_ST_BIND(esym->st_info),
1.102 + ELF32_ST_TYPE(esym->st_info));
1.103 +#endif
1.104 + if ((esym->st_value == 0) ||
1.105 + (ELF32_ST_BIND(esym->st_info) == STB_WEAK) ||
1.106 + (ELF32_ST_BIND(esym->st_info) == STB_NUM) ||
1.107 + (ELF32_ST_TYPE(esym->st_info) != STT_FUNC)) {
1.108 + continue;
1.109 + }
1.110 +#if 1
1.111 + char *nm = elf_strptr(elf, strtabndx, (size_t)esym->st_name);
1.112 +#endif
1.113 + sp->name = nm ? strdup(nm) : "(no name)";
1.114 + sp->address = esym->st_value;
1.115 + sp++;
1.116 + if (sp >= last) {
1.117 + long n = alloced + 10000;
1.118 + syms = (Symbol*)
1.119 + realloc(syms, (size_t) (sizeof(Symbol) * n));
1.120 + last = syms + n;
1.121 + sp = syms + alloced;
1.122 + alloced = n;
1.123 + }
1.124 + }
1.125 + }
1.126 + }
1.127 +
1.128 + int interesting = sp - syms;
1.129 + if (!quiet) {
1.130 + printf("Total of %d symbols\n", interesting);
1.131 + }
1.132 + usefulSymbols = interesting;
1.133 + externalSymbols = syms;
1.134 +}
1.135 +
1.136 +#endif /* USE_ELF */
