Move elfload into tools/

[netwatch.git] / tools / elfload.c

diff --git a/tools/elfload.c b/tools/elfload.c
new file mode 100644 (file)
index 0000000..c70571d
--- /dev/null
+++ b/tools/elfload.c
@@ -0,0 +1,104 @@
+#include <string.h>
+#include <stdio.h>
+#include "../include/elf.h"
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <termios.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#define FATAL do { fprintf(stderr, "Error at %s:%d (%d) [%s]\n", \
+  __FILE__, __LINE__, errno, strerror(errno)); exit(1); } while(0)
+
+#define MAP_SIZE 131072
+#define MAP_MASK (4096 - 1)
+
+char * snarf_file(char * fname) {
+
+       int fd = open(fname, O_RDONLY);
+       if (fd < 0) FATAL;
+
+       struct stat st;
+       if (fstat(fd, &st) < 0) FATAL;
+
+       char * buf = malloc(st.st_size);
+       if (!buf) FATAL;
+       if (read(fd, buf, st.st_size) != st.st_size) FATAL;
+
+       printf("Loaded %d bytes.\n", st.st_size);
+       return buf;
+}
+
+void dump_to_ram (void * src, int target, int size) {
+
+       printf("Copying %d bytes to 0x%08x...\n", size, target);
+
+       int fd = open("/dev/mem", O_RDWR | O_SYNC);
+        if (fd < 0) FATAL;
+
+        void * map_base = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE,
+                               MAP_SHARED, fd, target & ~MAP_MASK);
+
+        if (map_base == (void *) -1) FATAL;
+
+        void * virt_addr = map_base + (target & MAP_MASK);
+        memcpy(virt_addr, src, size);
+
+}
+
+static const unsigned char elf_ident[4] = { 0x7F, 'E', 'L', 'F' }; 
+
+int load_elf (char * buf) {
+
+       Elf32_Ehdr * elf_hdr = (Elf32_Ehdr *) buf;
+       Elf32_Shdr * elf_sec_hdrs = (Elf32_Shdr *) (buf + elf_hdr->e_shoff);
+
+       if (memcmp(elf_hdr->e_ident, elf_ident, sizeof(elf_ident))) FATAL;
+       if (elf_hdr->e_type != ET_EXEC) FATAL;
+       if (elf_hdr->e_machine != EM_386) FATAL;
+       if (elf_hdr->e_version != EV_CURRENT) FATAL;
+
+       char * string_table = buf + elf_sec_hdrs[elf_hdr->e_shstrndx].sh_offset;
+
+       int i;
+       for (i = 0; i < elf_hdr->e_shnum; i++) {
+               if (elf_sec_hdrs[i].sh_name == SHN_UNDEF) {
+                       continue;
+               }
+
+               char * section_name = string_table + elf_sec_hdrs[i].sh_name;
+
+               if ((elf_sec_hdrs[i].sh_type != SHT_PROGBITS) || !(elf_sec_hdrs[i].sh_flags & SHF_ALLOC)) {
+                       printf("Skipping %s...\n", section_name);
+                       continue;
+               }
+
+               printf("Loading %s...\n", section_name);
+
+               dump_to_ram(buf + elf_sec_hdrs[i].sh_offset,
+                           elf_sec_hdrs[i].sh_addr,
+                           elf_sec_hdrs[i].sh_size);
+       }
+
+       return 0;
+}
+
+int main(int argc, char **argv) {
+       if (argc != 2) {
+               printf("Usage: %s elffile\n", argv[0]);
+               return 1;
+       }
+
+       printf("Loading file...\n");
+
+       char * buf = snarf_file(argv[1]);
+       load_elf(buf);
+
+       return 0;
+}
+