add zpm-soneed

[zpackage] / elf / libelf.c

diff --git a/elf/libelf.c b/elf/libelf.c
new file mode 100644 (file)
index 0000000..477344f
--- /dev/null
+++ b/elf/libelf.c
@@ -0,0 +1,135 @@
+#define _POSIX_C_SOURCE 200112L
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "elf.h"
+
+void *libelf_map(char *path, size_t *fsize);
+int libelf_iself(void *elf);
+char *libelf_soname(void *elf);
+int libelf_type(void *elf);
+
+Elf64_Ehdr *libelf_header(void *elf) {
+       return elf;
+}
+
+Elf64_Shdr *libelf_shdr(void *elf, int n) {
+       return 0;
+}
+
+Elf64_Shdr *libelf_sht_strtab(void *elf) {
+       int i;
+       Elf64_Ehdr *hdr;
+       Elf64_Shdr *shdr;
+
+       hdr = libelf_header(elf);
+
+       for (i = 0; i < hdr->e_shnum; i++) {
+               shdr = (Elf64_Shdr *)((char *)elf + hdr->e_shoff + i * hdr->e_shentsize);
+               if (shdr->sh_type == SHT_STRTAB && i == hdr->e_shstrndx) {
+                       return shdr;
+               }
+       }
+       return 0;
+}
+
+char *libelf_sectionname(Elf64_Shdr *section, Elf64_Shdr *strtab) {
+       return (char *)strtab + section->sh_name;
+}
+
+Elf64_Shdr *libelf_section_n(void *elf, int n) {
+       Elf64_Ehdr *hdr;
+
+       hdr = libelf_header(elf);
+
+       if (n > hdr->e_shnum) {
+               return 0;
+       }
+
+       return (Elf64_Shdr *)((char *)elf + hdr->e_shoff + n * hdr->e_shentsize);
+}
+
+Elf64_Shdr *libelf_section(void *elf, int type) {
+       int i;
+       Elf64_Ehdr *hdr;
+       Elf64_Shdr *shdr;
+
+       hdr = libelf_header(elf);
+
+       for (i = 0; i < hdr->e_shnum; i++) {
+               shdr = (Elf64_Shdr *)((char *)elf + hdr->e_shoff + i * hdr->e_shentsize);
+               if (shdr->sh_type == type) {
+                       return shdr;
+               }
+       }
+       return 0;
+}
+
+int libelf_type(void *elf) {
+       return ((Elf64_Ehdr *)elf)->e_type;
+}
+
+int libelf_iself(void *elf) {
+       Elf64_Ehdr *hdr;
+       hdr = elf;
+       if (hdr->e_ident[EI_MAG0] != ELFMAG0
+                       || hdr->e_ident[EI_MAG1] != ELFMAG1
+                       || hdr->e_ident[EI_MAG2] != ELFMAG2
+                       || hdr->e_ident[EI_MAG3] != ELFMAG3
+          ) {
+               return 0;
+       }
+       return 1;
+}
+
+void *libelf_map(char *path, size_t *fsize) {
+       int elffd;
+       struct stat sbuf;
+       void *elfbase;
+
+       errno = 0;
+
+       elffd = open(path, O_RDONLY);
+       if (elffd == -1) {
+               perror("open");
+               return NULL;
+       }
+       if (fstat(elffd, &sbuf) == -1) {
+               close(elffd);
+               return NULL;
+       }
+       /* not a regular file? */
+       if (!S_ISREG(sbuf.st_mode)) {
+               close(elffd);
+               return NULL;
+       }
+       /* not at least the size of the elf header? */
+       if (sbuf.st_size < sizeof(Elf64_Ehdr)) {
+               close(elffd);
+               return NULL;
+       }
+
+       elfbase = mmap(0, sbuf.st_size, PROT_READ,MAP_PRIVATE, elffd, 0);
+       close(elffd);
+       if (!elfbase) {
+               return NULL;
+       }
+
+       if (!libelf_iself(elfbase)) {
+               munmap(elfbase, sbuf.st_size);
+               return NULL;
+       }
+
+       *fsize = sbuf.st_size;
+
+       return elfbase;
+}