/usr.bin/gprof/elf.c
https://bitbucket.org/freebsd/freebsd-head/ · C · 144 lines · 89 code · 21 blank · 34 comment · 25 complexity · 8894d886a820500463d859a6f3a818dc MD5 · raw file
- /*-
- * Copyright (c) 1983, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
- #if 0
- /* From: */
- #ifndef lint
- static char sccsid[] = "@(#)gprof.c 8.1 (Berkeley) 6/6/93";
- #endif /* not lint */
- #endif
- #include <sys/cdefs.h>
- __FBSDID("$FreeBSD$");
- #include <sys/types.h>
- #include <sys/mman.h>
- #include <sys/stat.h>
- #include <machine/elf.h>
- #include <err.h>
- #include <fcntl.h>
- #include <string.h>
- #include <unistd.h>
- #include "gprof.h"
- static bool wantsym(const Elf_Sym *, const char *);
- /* Things which get -E excluded by default. */
- static char *excludes[] = { ".mcount", "_mcleanup", NULL };
- int
- elf_getnfile(const char *filename, char ***defaultEs)
- {
- int fd;
- Elf_Ehdr h;
- struct stat s;
- void *mapbase;
- const char *base;
- const Elf_Shdr *shdrs;
- const Elf_Shdr *sh_symtab;
- const Elf_Shdr *sh_strtab;
- const char *strtab;
- const Elf_Sym *symtab;
- int symtabct;
- int i;
- if ((fd = open(filename, O_RDONLY)) == -1)
- err(1, "%s", filename);
- if (read(fd, &h, sizeof h) != sizeof h || !IS_ELF(h)) {
- close(fd);
- return -1;
- }
- if (fstat(fd, &s) == -1)
- err(1, "cannot fstat %s", filename);
- if ((mapbase = mmap(0, s.st_size, PROT_READ, MAP_SHARED, fd, 0)) ==
- MAP_FAILED)
- err(1, "cannot mmap %s", filename);
- close(fd);
- base = (const char *)mapbase;
- shdrs = (const Elf_Shdr *)(base + h.e_shoff);
- /* Find the symbol table and associated string table section. */
- for (i = 1; i < h.e_shnum; i++)
- if (shdrs[i].sh_type == SHT_SYMTAB)
- break;
- if (i == h.e_shnum)
- errx(1, "%s has no symbol table", filename);
- sh_symtab = &shdrs[i];
- sh_strtab = &shdrs[sh_symtab->sh_link];
- symtab = (const Elf_Sym *)(base + sh_symtab->sh_offset);
- symtabct = sh_symtab->sh_size / sh_symtab->sh_entsize;
- strtab = (const char *)(base + sh_strtab->sh_offset);
- /* Count the symbols that we're interested in. */
- nname = 0;
- for (i = 1; i < symtabct; i++)
- if (wantsym(&symtab[i], strtab))
- nname++;
- /* Allocate memory for them, plus a terminating entry. */
- if ((nl = (nltype *)calloc(nname + 1, sizeof(nltype))) == NULL)
- errx(1, "insufficient memory for symbol table");
- /* Read them in. */
- npe = nl;
- for (i = 1; i < symtabct; i++) {
- const Elf_Sym *sym = &symtab[i];
- if (wantsym(sym, strtab)) {
- npe->value = sym->st_value;
- npe->name = strtab + sym->st_name;
- npe++;
- }
- }
- npe->value = -1;
- *defaultEs = excludes;
- return 0;
- }
- static bool
- wantsym(const Elf_Sym *sym, const char *strtab)
- {
- int type;
- int bind;
- type = ELF_ST_TYPE(sym->st_info);
- bind = ELF_ST_BIND(sym->st_info);
- if (type != STT_FUNC ||
- (aflag && bind == STB_LOCAL) ||
- (uflag && strchr(strtab + sym->st_name, '.') != NULL))
- return 0;
- return 1;
- }