Commit a610993d authored by Geoff Voelker's avatar Geoff Voelker
Browse files

(get_bss_info_from_map_file): New function.

(get_section_info): When .bss section parameters are not in the
executable, search the symbol map file for them.
parent b72535bc
......@@ -291,6 +291,44 @@ close_file_data (file_data *p_file)
/* Routines to manipulate NT executable file sections. */
static void
get_bss_info_from_map_file (file_data *p_infile, PUCHAR *p_bss_start,
DWORD *p_bss_size)
int n, start, len;
char map_filename[MAX_PATH];
char buffer[256];
FILE *map;
/* Overwrite the .exe extension on the executable file name with
the .map extension. */
strcpy (map_filename, p_infile->name);
n = strlen (map_filename) - 3;
strcpy (&map_filename[n], "map");
map = fopen (map_filename, "r");
if (!map)
printf ("Failed to open map file %s, error %d...bailing out.\n",
map_filename, GetLastError ());
exit (-1);
while (fgets (buffer, sizeof (buffer), map))
if (!(strstr (buffer, ".bss") && strstr (buffer, "DATA")))
n = sscanf (buffer, " %*d:%x %x", &start, &len);
if (n != 2)
printf ("Failed to scan the .bss section line:\n%s", buffer);
exit (-1);
*p_bss_start = (PUCHAR) start;
*p_bss_size = (DWORD) len;
static unsigned long
get_section_size (PIMAGE_SECTION_HEADER p_section)
......@@ -311,7 +349,7 @@ get_section_info (file_data *p_infile)
PIMAGE_SECTION_HEADER section, data_section;
unsigned char *ptr;
int i;
......@@ -355,6 +393,7 @@ get_section_info (file_data *p_infile)
extern char my_edata[];
/* The .data section. */
data_section = section;
ptr = (char *) nt_header->OptionalHeader.ImageBase +
data_start_va = ptr;
......@@ -368,6 +407,21 @@ get_section_info (file_data *p_infile)
if (!bss_start && !bss_size)
/* Starting with MSVC 4.0, the .bss section has been eliminated
and appended virtually to the end of the .data section. Our
only hint about where the .bss section starts in the address
comes from the SizeOfRawData field in the .data section
header. Unfortunately, this field is only approximate, as it
is a rounded number and is typically rounded just beyond the
start of the .bss section. To find the start and size of the
.bss section exactly, we have to peek into the map file. */
get_bss_info_from_map_file (p_infile, &ptr, &bss_size);
bss_start = ptr + nt_header->OptionalHeader.ImageBase
+ data_section->VirtualAddress;
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