1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/tools/jprof/bfd.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,231 @@
1.4 +// vim:ts=8:sw=2:et:
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "leaky.h"
1.10 +
1.11 +#ifdef USE_BFD
1.12 +#include <stdio.h>
1.13 +#include <string.h>
1.14 +#include <fcntl.h>
1.15 +#include <unistd.h>
1.16 +#include <libgen.h>
1.17 +#include <bfd.h>
1.18 +#include <cxxabi.h>
1.19 +
1.20 +static bfd *try_debug_file(const char *filename, unsigned long crc32)
1.21 +{
1.22 + int fd = open(filename, O_RDONLY);
1.23 + if (fd < 0)
1.24 + return nullptr;
1.25 +
1.26 + unsigned char buf[4*1024];
1.27 + unsigned long crc = 0;
1.28 +
1.29 + while (1) {
1.30 + ssize_t count = read(fd, buf, sizeof(buf));
1.31 + if (count <= 0)
1.32 + break;
1.33 +
1.34 + crc = bfd_calc_gnu_debuglink_crc32(crc, buf, count);
1.35 + }
1.36 +
1.37 + close(fd);
1.38 +
1.39 + if (crc != crc32)
1.40 + return nullptr;
1.41 +
1.42 + bfd *object = bfd_openr(filename, nullptr);
1.43 + if (!bfd_check_format(object, bfd_object)) {
1.44 + bfd_close(object);
1.45 + return nullptr;
1.46 + }
1.47 +
1.48 + return object;
1.49 +}
1.50 +
1.51 +static bfd *find_debug_file(bfd *lib, const char *aFileName)
1.52 +{
1.53 + // check for a separate debug file with symbols
1.54 + asection *sect = bfd_get_section_by_name(lib, ".gnu_debuglink");
1.55 +
1.56 + if (!sect)
1.57 + return nullptr;
1.58 +
1.59 + bfd_size_type debuglinkSize = bfd_section_size (objfile->obfd, sect);
1.60 +
1.61 + char *debuglink = new char[debuglinkSize];
1.62 + bfd_get_section_contents(lib, sect, debuglink, 0, debuglinkSize);
1.63 +
1.64 + // crc checksum is aligned to 4 bytes, and after the NUL.
1.65 + int crc_offset = (int(strlen(debuglink)) & ~3) + 4;
1.66 + unsigned long crc32 = bfd_get_32(lib, debuglink + crc_offset);
1.67 +
1.68 + // directory component
1.69 + char *dirbuf = strdup(aFileName);
1.70 + const char *dir = dirname(dirbuf);
1.71 +
1.72 + static const char debug_subdir[] = ".debug";
1.73 + // This is gdb's default global debugging info directory, but gdb can
1.74 + // be instructed to use a different directory.
1.75 + static const char global_debug_dir[] = "/usr/lib/debug";
1.76 +
1.77 + char *filename =
1.78 + new char[strlen(global_debug_dir) + strlen(dir) + crc_offset + 3];
1.79 +
1.80 + // /path/debuglink
1.81 + sprintf(filename, "%s/%s", dir, debuglink);
1.82 + bfd *debugFile = try_debug_file(filename, crc32);
1.83 + if (!debugFile) {
1.84 +
1.85 + // /path/.debug/debuglink
1.86 + sprintf(filename, "%s/%s/%s", dir, debug_subdir, debuglink);
1.87 + debugFile = try_debug_file(filename, crc32);
1.88 + if (!debugFile) {
1.89 +
1.90 + // /usr/lib/debug/path/debuglink
1.91 + sprintf(filename, "%s/%s/%s", global_debug_dir, dir, debuglink);
1.92 + debugFile = try_debug_file(filename, crc32);
1.93 + }
1.94 + }
1.95 +
1.96 + delete[] filename;
1.97 + free(dirbuf);
1.98 + delete[] debuglink;
1.99 +
1.100 + return debugFile;
1.101 +}
1.102 +
1.103 +
1.104 +// Use an indirect array to avoid copying tons of objects
1.105 +Symbol ** leaky::ExtendSymbols(int num)
1.106 +{
1.107 + long n = numExternalSymbols + num;
1.108 +
1.109 + externalSymbols = (Symbol**)
1.110 + realloc(externalSymbols,
1.111 + (size_t) (sizeof(externalSymbols[0]) * n));
1.112 + Symbol *new_array = new Symbol[n];
1.113 + for (int i = 0; i < num; i++) {
1.114 + externalSymbols[i + numExternalSymbols] = &new_array[i];
1.115 + }
1.116 + lastSymbol = externalSymbols + n;
1.117 + Symbol **sp = externalSymbols + numExternalSymbols;
1.118 + numExternalSymbols = n;
1.119 + return sp;
1.120 +}
1.121 +
1.122 +#define NEXT_SYMBOL do { sp++; \
1.123 + if (sp >= lastSymbol) { \
1.124 + sp = ExtendSymbols(16384); \
1.125 + } \
1.126 + } while (0)
1.127 +
1.128 +void leaky::ReadSymbols(const char *aFileName, u_long aBaseAddress)
1.129 +{
1.130 + int initialSymbols = usefulSymbols;
1.131 + if (nullptr == externalSymbols) {
1.132 + externalSymbols = (Symbol**) calloc(sizeof(Symbol*),10000);
1.133 + Symbol *new_array = new Symbol[10000];
1.134 + for (int i = 0; i < 10000; i++) {
1.135 + externalSymbols[i] = &new_array[i];
1.136 + }
1.137 + numExternalSymbols = 10000;
1.138 + }
1.139 + Symbol** sp = externalSymbols + usefulSymbols;
1.140 + lastSymbol = externalSymbols + numExternalSymbols;
1.141 +
1.142 + // Create a dummy symbol for the library so, if it doesn't have any
1.143 + // symbols, we show it by library.
1.144 + (*sp)->Init(aFileName, aBaseAddress);
1.145 + NEXT_SYMBOL;
1.146 +
1.147 + bfd_boolean kDynamic = (bfd_boolean) false;
1.148 +
1.149 + static int firstTime = 1;
1.150 + if (firstTime) {
1.151 + firstTime = 0;
1.152 + bfd_init ();
1.153 + }
1.154 +
1.155 + bfd* lib = bfd_openr(aFileName, nullptr);
1.156 + if (nullptr == lib) {
1.157 + return;
1.158 + }
1.159 + if (!bfd_check_format(lib, bfd_object)) {
1.160 + bfd_close(lib);
1.161 + return;
1.162 + }
1.163 +
1.164 + bfd *symbolFile = find_debug_file(lib, aFileName);
1.165 +
1.166 + // read mini symbols
1.167 + PTR minisyms;
1.168 + unsigned int size;
1.169 + long symcount = 0;
1.170 +
1.171 + if (symbolFile) {
1.172 + symcount = bfd_read_minisymbols(symbolFile, kDynamic, &minisyms, &size);
1.173 + if (symcount == 0) {
1.174 + bfd_close(symbolFile);
1.175 + } else {
1.176 + bfd_close(lib);
1.177 + }
1.178 + }
1.179 + if (symcount == 0) {
1.180 + symcount = bfd_read_minisymbols(lib, kDynamic, &minisyms, &size);
1.181 + if (symcount == 0) {
1.182 + // symtab is empty; try dynamic symbols
1.183 + kDynamic = (bfd_boolean) true;
1.184 + symcount = bfd_read_minisymbols(lib, kDynamic, &minisyms, &size);
1.185 + }
1.186 + symbolFile = lib;
1.187 + }
1.188 +
1.189 + asymbol* store;
1.190 + store = bfd_make_empty_symbol(symbolFile);
1.191 +
1.192 + // Scan symbols
1.193 + size_t demangle_buffer_size = 128;
1.194 + char *demangle_buffer = (char*) malloc(demangle_buffer_size);
1.195 + bfd_byte* from = (bfd_byte *) minisyms;
1.196 + bfd_byte* fromend = from + symcount * size;
1.197 + for (; from < fromend; from += size) {
1.198 + asymbol *sym;
1.199 + sym = bfd_minisymbol_to_symbol(symbolFile, kDynamic, (const PTR) from, store);
1.200 +
1.201 + symbol_info syminfo;
1.202 + bfd_get_symbol_info (symbolFile, sym, &syminfo);
1.203 +
1.204 +// if ((syminfo.type == 'T') || (syminfo.type == 't')) {
1.205 + const char* nm = bfd_asymbol_name(sym);
1.206 + if (nm && nm[0]) {
1.207 + char* dnm = nullptr;
1.208 + if (strncmp("__thunk", nm, 7)) {
1.209 + dnm =
1.210 + abi::__cxa_demangle(nm, demangle_buffer, &demangle_buffer_size, 0);
1.211 + if (dnm) {
1.212 + demangle_buffer = dnm;
1.213 + }
1.214 + }
1.215 + (*sp)->Init(dnm ? dnm : nm, syminfo.value + aBaseAddress);
1.216 + NEXT_SYMBOL;
1.217 + }
1.218 +// }
1.219 + }
1.220 +
1.221 + free(demangle_buffer);
1.222 + demangle_buffer = nullptr;
1.223 +
1.224 + bfd_close(symbolFile);
1.225 +
1.226 + int interesting = sp - externalSymbols;
1.227 + if (!quiet) {
1.228 + printf("%s provided %d symbols\n", aFileName,
1.229 + interesting - initialSymbols);
1.230 + }
1.231 + usefulSymbols = interesting;
1.232 +}
1.233 +
1.234 +#endif /* USE_BFD */
