By using elf files, we make it easier to disassemble
the test file, to match comparison failures to code.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
risu.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 52 insertions(+), 5 deletions(-)
diff --git a/risu.c b/risu.c
index c28b4a5..c9c3a38 100644
--- a/risu.c
+++ b/risu.c
@@ -24,6 +24,15 @@
#include <sys/mman.h>
#include <fcntl.h>
#include <string.h>
+#include <elf.h>
+
+/* TODO: Improve configure. */
+#ifdef __linux__
+#include <endian.h>
+#define HOST_BIG_ENDIAN (__BYTE_ORDER == __BIG_ENDIAN)
+#else
+#error Need HOST_BIG_ENDIAN
+#endif
#include "config.h"
#include "risu.h"
@@ -346,8 +355,11 @@ static void load_image(const char *imgfile)
{
/* Load image file into memory as executable */
struct stat st;
+ void *addr;
+ int fd;
+
fprintf(stderr, "loading test image %s...\n", imgfile);
- int fd = open(imgfile, O_RDONLY);
+ fd = open(imgfile, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "failed to open image file %s\n", imgfile);
exit(EXIT_FAILURE);
@@ -356,20 +368,55 @@ static void load_image(const char *imgfile)
perror("fstat");
exit(EXIT_FAILURE);
}
- size_t len = st.st_size;
- void *addr;
/* Map writable because we include the memory area for store
* testing in the image.
*/
- addr = mmap(0, len, PROT_READ | PROT_WRITE | PROT_EXEC,
+ addr = mmap(0, st.st_size, PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE, fd, 0);
if (addr == MAP_FAILED) {
perror("mmap");
exit(EXIT_FAILURE);
}
close(fd);
- image_start = addr;
+
+ if (memcmp(addr, ELFMAG, SELFMAG) == 0) {
+ union {
+ unsigned char ident[EI_NIDENT];
+ Elf32_Ehdr h32;
+ Elf64_Ehdr h64;
+ } *e = addr;
+ size_t entry;
+
+ /*
+ * TODO: More complete parsing of ELF file, verify assumtion, namely:
+ * Single PT_LOAD covering the ELF header, code and data.
+ * For now, simply update image_start from the elf header.
+ */
+ if (e->ident[EI_DATA] !=
+ (HOST_BIG_ENDIAN ? ELFDATA2MSB : ELFDATA2LSB)) {
+ fprintf(stderr, "%s: Endian mismatch: EI_DATA = %x\n",
+ imgfile, e->ident[EI_DATA]);
+ exit(1);
+ }
+
+ switch (e->ident[EI_CLASS]) {
+ case ELFCLASS32:
+ entry = e->h32.e_entry;
+ break;
+ case ELFCLASS64:
+ entry = e->h64.e_entry;
+ break;
+ default:
+ fprintf(stderr, "%s: Bad elf header: EI_CLASS = %x\n",
+ imgfile, e->ident[EI_CLASS]);
+ exit(1);
+ }
+ image_start = addr + entry;
+ } else {
+ /* Raw binary image. */
+ image_start = addr;
+ }
image_start_address = (uintptr_t) addr;
}
--
2.34.1