Mercurial > hg > truffle
view agent/src/os/linux/symtab.c @ 6190:61a94c2da7c4
7179759: ENV: Nightly fails during jdk copiyng for solaris platforms after FDS unzipping
Summary: libjvm_g_db.so and libjvm_g_dtrace.so links in .diz file still had 64 directory
Reviewed-by: kamg, dholmes, sspitsyn
author | coleenp |
---|---|
date | Fri, 29 Jun 2012 14:28:10 -0700 |
parents | 0a8e0d4345b3 |
children | f2512d89ad0c |
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/* * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include <unistd.h> #include <sys/procfs.h> #include <search.h> #include <stdlib.h> #include <string.h> #include "symtab.h" #include "salibelf.h" // ---------------------------------------------------- // functions for symbol lookups // ---------------------------------------------------- struct elf_section { ELF_SHDR *c_shdr; void *c_data; }; struct elf_symbol { char *name; uintptr_t offset; uintptr_t size; }; typedef struct symtab { char *strs; size_t num_symbols; struct elf_symbol *symbols; struct hsearch_data *hash_table; } symtab_t; // Directory that contains global debuginfo files. In theory it // should be possible to change this, but in a Java environment there // is no obvious place to put a user interface to do it. Maybe this // could be set with an environment variable. static const char debug_file_directory[] = "/usr/lib/debug"; /* The CRC used in gnu_debuglink, retrieved from http://sourceware.org/gdb/current/onlinedocs/gdb/Separate-Debug-Files.html#Separate-Debug-Files. */ unsigned int gnu_debuglink_crc32 (unsigned int crc, unsigned char *buf, size_t len) { static const unsigned int crc32_table[256] = { 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d }; unsigned char *end; crc = ~crc & 0xffffffff; for (end = buf + len; buf < end; ++buf) crc = crc32_table[(crc ^ *buf) & 0xff] ^ (crc >> 8); return ~crc & 0xffffffff; } /* Open a debuginfo file and check its CRC. If it exists and the CRC matches return its fd. */ static int open_debug_file (const char *pathname, unsigned int crc) { unsigned int file_crc = 0; unsigned char buffer[8 * 1024]; int fd = pathmap_open(pathname); if (fd < 0) return -1; lseek(fd, 0, SEEK_SET); for (;;) { int len = read(fd, buffer, sizeof buffer); if (len <= 0) break; file_crc = gnu_debuglink_crc32(file_crc, buffer, len); } if (crc == file_crc) return fd; else { close(fd); return -1; } } /* Find an ELF section. */ static struct elf_section *find_section_by_name(char *name, int fd, ELF_EHDR *ehdr, ELF_SHDR *shbuf, struct elf_section *scn_cache) { ELF_SHDR* cursct = NULL; char *strtab; int cnt; if (scn_cache[ehdr->e_shstrndx].c_data == NULL) { if ((scn_cache[ehdr->e_shstrndx].c_data = read_section_data(fd, ehdr, cursct)) == NULL) { return NULL; } } strtab = scn_cache[ehdr->e_shstrndx].c_data; for (cursct = shbuf, cnt = 0; cnt < ehdr->e_shnum; cnt++, cursct++) { if (strcmp(cursct->sh_name + strtab, name) == 0) { scn_cache[cnt].c_data = read_section_data(fd, ehdr, cursct); return &scn_cache[cnt]; } } return NULL; } /* Look for a ".gnu_debuglink" section. If one exists, try to open a suitable debuginfo file. */ static int open_file_from_debug_link(const char *name, int fd, ELF_EHDR *ehdr, ELF_SHDR *shbuf, struct elf_section *scn_cache) { int debug_fd; struct elf_section *debug_link = find_section_by_name(".gnu_debuglink", fd, ehdr, shbuf, scn_cache); if (debug_link == NULL) return -1; char *debug_filename = debug_link->c_data; int offset = (strlen(debug_filename) + 4) >> 2; static unsigned int crc; crc = ((unsigned int*)debug_link->c_data)[offset]; char *debug_pathname = malloc(strlen(debug_filename) + strlen(name) + strlen(".debug/") + strlen(debug_file_directory) + 2); strcpy(debug_pathname, name); char *last_slash = strrchr(debug_pathname, '/'); if (last_slash == NULL) return -1; /* Look in the same directory as the object. */ strcpy(last_slash+1, debug_filename); debug_fd = open_debug_file(debug_pathname, crc); if (debug_fd >= 0) { free(debug_pathname); return debug_fd; } /* Look in a subdirectory named ".debug". */ strcpy(last_slash+1, ".debug/"); strcat(last_slash, debug_filename); debug_fd = open_debug_file(debug_pathname, crc); if (debug_fd >= 0) { free(debug_pathname); return debug_fd; } /* Look in /usr/lib/debug + the full pathname. */ strcpy(debug_pathname, debug_file_directory); strcat(debug_pathname, name); last_slash = strrchr(debug_pathname, '/'); strcpy(last_slash+1, debug_filename); debug_fd = open_debug_file(debug_pathname, crc); if (debug_fd >= 0) { free(debug_pathname); return debug_fd; } free(debug_pathname); return -1; } static struct symtab* build_symtab_internal(int fd, const char *filename, bool try_debuginfo); /* Look for a ".gnu_debuglink" section. If one exists, try to open a suitable debuginfo file and read a symbol table from it. */ static struct symtab *build_symtab_from_debug_link(const char *name, int fd, ELF_EHDR *ehdr, ELF_SHDR *shbuf, struct elf_section *scn_cache) { fd = open_file_from_debug_link(name, fd, ehdr, shbuf, scn_cache); if (fd >= 0) { struct symtab *symtab = build_symtab_internal(fd, NULL, /* try_debuginfo */ false); close(fd); return symtab; } return NULL; } // Given a build_id, find the associated debuginfo file static char * build_id_to_debug_filename (size_t size, unsigned char *data) { char *filename, *s; filename = malloc(strlen (debug_file_directory) + (sizeof "/.build-id/" - 1) + 1 + 2 * size + (sizeof ".debug" - 1) + 1); s = filename + sprintf (filename, "%s/.build-id/", debug_file_directory); if (size > 0) { size--; s += sprintf (s, "%02x", *data++); } if (size > 0) *s++ = '/'; while (size-- > 0) s += sprintf (s, "%02x", *data++); strcpy (s, ".debug"); return filename; } // Read a build ID note. Try to open any associated debuginfo file // and return its symtab static struct symtab* build_symtab_from_build_id(Elf64_Nhdr *note) { int fd; struct symtab *symtab = NULL; unsigned char *bytes = (unsigned char*)(note+1) + note->n_namesz; unsigned char *filename = (build_id_to_debug_filename (note->n_descsz, bytes)); fd = pathmap_open(filename); if (fd >= 0) { symtab = build_symtab_internal(fd, NULL, /* try_debuginfo */ false); close(fd); } free(filename); return symtab; } // read symbol table from given fd. If try_debuginfo) is true, also // try to open an associated debuginfo file static struct symtab* build_symtab_internal(int fd, const char *filename, bool try_debuginfo) { ELF_EHDR ehdr; char *names = NULL; struct symtab* symtab = NULL; // Reading of elf header struct elf_section *scn_cache = NULL; int cnt = 0; ELF_SHDR* shbuf = NULL; ELF_SHDR* cursct = NULL; ELF_PHDR* phbuf = NULL; ELF_PHDR* phdr = NULL; int sym_section = SHT_DYNSYM; uintptr_t baseaddr = (uintptr_t)-1; lseek(fd, (off_t)0L, SEEK_SET); if (! read_elf_header(fd, &ehdr)) { // not an elf return NULL; } // read ELF header if ((shbuf = read_section_header_table(fd, &ehdr)) == NULL) { goto quit; } baseaddr = find_base_address(fd, &ehdr); scn_cache = (struct elf_section *) calloc(ehdr.e_shnum * sizeof(struct elf_section), 1); if (scn_cache == NULL) { goto quit; } for (cursct = shbuf, cnt = 0; cnt < ehdr.e_shnum; cnt++) { scn_cache[cnt].c_shdr = cursct; if (cursct->sh_type == SHT_SYMTAB || cursct->sh_type == SHT_STRTAB || cursct->sh_type == SHT_NOTE || cursct->sh_type == SHT_DYNSYM) { if ( (scn_cache[cnt].c_data = read_section_data(fd, &ehdr, cursct)) == NULL) { goto quit; } } if (cursct->sh_type == SHT_SYMTAB) { // Full symbol table available so use that sym_section = cursct->sh_type; } cursct++; } for (cnt = 1; cnt < ehdr.e_shnum; cnt++) { ELF_SHDR *shdr = scn_cache[cnt].c_shdr; if (shdr->sh_type == sym_section) { ELF_SYM *syms; int j, n, rslt; size_t size; // FIXME: there could be multiple data buffers associated with the // same ELF section. Here we can handle only one buffer. See man page // for elf_getdata on Solaris. // guarantee(symtab == NULL, "multiple symtab"); symtab = (struct symtab*)calloc(1, sizeof(struct symtab)); if (symtab == NULL) { goto quit; } // the symbol table syms = (ELF_SYM *)scn_cache[cnt].c_data; // number of symbols n = shdr->sh_size / shdr->sh_entsize; // create hash table, we use hcreate_r, hsearch_r and hdestroy_r to // manipulate the hash table. symtab->hash_table = (struct hsearch_data*) calloc(1, sizeof(struct hsearch_data)); rslt = hcreate_r(n, symtab->hash_table); // guarantee(rslt, "unexpected failure: hcreate_r"); // shdr->sh_link points to the section that contains the actual strings // for symbol names. the st_name field in ELF_SYM is just the // string table index. we make a copy of the string table so the // strings will not be destroyed by elf_end. size = scn_cache[shdr->sh_link].c_shdr->sh_size; symtab->strs = (char *)malloc(size); memcpy(symtab->strs, scn_cache[shdr->sh_link].c_data, size); // allocate memory for storing symbol offset and size; symtab->num_symbols = n; symtab->symbols = (struct elf_symbol *)calloc(n , sizeof(struct elf_symbol)); // copy symbols info our symtab and enter them info the hash table for (j = 0; j < n; j++, syms++) { ENTRY item, *ret; char *sym_name = symtab->strs + syms->st_name; // skip non-object and non-function symbols int st_type = ELF_ST_TYPE(syms->st_info); if ( st_type != STT_FUNC && st_type != STT_OBJECT) continue; // skip empty strings and undefined symbols if (*sym_name == '\0' || syms->st_shndx == SHN_UNDEF) continue; symtab->symbols[j].name = sym_name; symtab->symbols[j].offset = syms->st_value - baseaddr; symtab->symbols[j].size = syms->st_size; item.key = sym_name; item.data = (void *)&(symtab->symbols[j]); hsearch_r(item, ENTER, &ret, symtab->hash_table); } } } // Look for a separate debuginfo file. if (try_debuginfo) { // We prefer a debug symtab to an object's own symtab, so look in // the debuginfo file. We stash a copy of the old symtab in case // there is no debuginfo. struct symtab* prev_symtab = symtab; symtab = NULL; #ifdef NT_GNU_BUILD_ID // First we look for a Build ID for (cursct = shbuf, cnt = 0; symtab == NULL && cnt < ehdr.e_shnum; cnt++) { if (cursct->sh_type == SHT_NOTE) { Elf64_Nhdr *note = (Elf64_Nhdr *)scn_cache[cnt].c_data; if (note->n_type == NT_GNU_BUILD_ID) { symtab = build_symtab_from_build_id(note); } } cursct++; } #endif // Then, if that doesn't work, the debug link if (symtab == NULL) { symtab = build_symtab_from_debug_link(filename, fd, &ehdr, shbuf, scn_cache); } // If we still haven't found a symtab, use the object's own symtab. if (symtab != NULL) { if (prev_symtab != NULL) destroy_symtab(prev_symtab); } else { symtab = prev_symtab; } } quit: if (shbuf) free(shbuf); if (phbuf) free(phbuf); if (scn_cache) { for (cnt = 0; cnt < ehdr.e_shnum; cnt++) { if (scn_cache[cnt].c_data != NULL) { free(scn_cache[cnt].c_data); } } free(scn_cache); } return symtab; } struct symtab* build_symtab(int fd, const char *filename) { return build_symtab_internal(fd, filename, /* try_debuginfo */ true); } void destroy_symtab(struct symtab* symtab) { if (!symtab) return; if (symtab->strs) free(symtab->strs); if (symtab->symbols) free(symtab->symbols); if (symtab->hash_table) { hdestroy_r(symtab->hash_table); free(symtab->hash_table); } free(symtab); } uintptr_t search_symbol(struct symtab* symtab, uintptr_t base, const char *sym_name, int *sym_size) { ENTRY item; ENTRY* ret = NULL; // library does not have symbol table if (!symtab || !symtab->hash_table) return (uintptr_t)NULL; item.key = (char*) strdup(sym_name); hsearch_r(item, FIND, &ret, symtab->hash_table); if (ret) { struct elf_symbol * sym = (struct elf_symbol *)(ret->data); uintptr_t rslt = (uintptr_t) ((char*)base + sym->offset); if (sym_size) *sym_size = sym->size; free(item.key); return rslt; } quit: free(item.key); return (uintptr_t) NULL; } const char* nearest_symbol(struct symtab* symtab, uintptr_t offset, uintptr_t* poffset) { int n = 0; if (!symtab) return NULL; for (; n < symtab->num_symbols; n++) { struct elf_symbol* sym = &(symtab->symbols[n]); if (sym->name != NULL && offset >= sym->offset && offset < sym->offset + sym->size) { if (poffset) *poffset = (offset - sym->offset); return sym->name; } } return NULL; }