* Modified heavily since then.
*
* Synopsis:
- * unexec (new_name, a_name, data_start, bss_start, entry_address)
- * char *new_name, *a_name;
- * unsigned data_start, bss_start, entry_address;
+ * unexec (const char *new_name, const char *old_name);
*
* Takes a snapshot of the program and makes an a.out format file in the
* file named by the string argument new_name.
* If a_name is non-NULL, the symbol table will be taken from the given file.
* On some machines, an existing a_name file is required.
*
- * The boundaries within the a.out file may be adjusted with the data_start
- * and bss_start arguments. Either or both may be given as 0 for defaults.
- *
- * Data_start gives the boundary between the text segment and the data
- * segment of the program. The text segment can contain shared, read-only
- * program code and literal data, while the data segment is always unshared
- * and unprotected. Data_start gives the lowest unprotected address.
- * The value you specify may be rounded down to a suitable boundary
- * as required by the machine you are using.
- *
- * Specifying zero for data_start means the boundary between text and data
- * should not be the same as when the program was loaded.
- *
- * Bss_start indicates how much of the data segment is to be saved in the
- * a.out file and restored when the program is executed. It gives the lowest
- * unsaved address, and is rounded up to a page boundary. The default when 0
- * is given assumes that the entire data segment is to be stored, including
- * the previous data and bss as well as any additional storage allocated with
- * break (2).
- *
- * The new file is set up to start at entry_address.
- *
* If you make improvements I'd like to get them too.
* harpo!utah-cs!thomas, thomas@Utah-20
*
#include <sys/file.h>
-#ifndef O_RDONLY
-#define O_RDONLY 0
-#endif
-#ifndef O_RDWR
-#define O_RDWR 2
-#endif
-
-
extern char *start_of_data (void); /* Start of initialized data */
static long block_copy_start; /* Old executable start point */
* Modify the text and data sizes.
*/
static int
-make_hdr (int new, int a_out, unsigned data_start, unsigned bss_start,
- unsigned entry_address, const char *a_name, const char *new_name)
+make_hdr (int new, int a_out,
+ const char *a_name, const char *new_name)
{
auto struct scnhdr f_thdr; /* Text section header */
auto struct scnhdr f_dhdr; /* Data section header */
auto struct scnhdr f_bhdr; /* Bss section header */
auto struct scnhdr scntemp; /* Temporary section header */
register int scns;
- unsigned int bss_end;
+ unsigned int bss_start;
+ unsigned int data_start;
pagemask = getpagesize () - 1;
data_start = ADDR_CORRECT (data_start);
data_start = data_start & ~pagemask; /* (Down) to page boundary. */
- bss_end = ADDR_CORRECT (sbrk (0)) + pagemask;
- bss_end &= ~ pagemask;
-
- /* Adjust data/bss boundary. */
- if (bss_start != 0)
- {
- bss_start = (ADDR_CORRECT (bss_start) + pagemask);
- /* (Up) to page bdry. */
- bss_start &= ~ pagemask;
- if (bss_start > bss_end)
- {
- ERROR1 ("unexec: Specified bss_start (%u) is past end of program",
- bss_start);
- }
- }
- else
- bss_start = bss_end;
+ bss_start = ADDR_CORRECT (sbrk (0)) + pagemask;
+ bss_start &= ~ pagemask;
if (data_start > bss_start) /* Can't have negative data size. */
{
f_hdr.f_flags |= (F_RELFLG | F_EXEC);
f_ohdr.dsize = bss_start - f_ohdr.data_start;
- f_ohdr.bsize = bss_end - bss_start;
+ f_ohdr.bsize = 0;
f_thdr.s_size = f_ohdr.tsize;
f_thdr.s_scnptr = sizeof (f_hdr) + sizeof (f_ohdr);
f_thdr.s_scnptr += (f_hdr.f_nscns) * (sizeof (f_thdr));
* driving logic.
*/
int
-unexec (const char *new_name, const char *a_name,
- unsigned data_start, unsigned bss_start, unsigned entry_address)
+unexec (const char *new_name, const char *a_name)
{
int new = -1, a_out = -1;
PERROR (new_name);
}
- if (make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) < 0
+ if (make_hdr (new, a_out, a_name, new_name) < 0
|| copy_text_and_data (new, a_out) < 0
|| copy_sym (new, a_out, a_name, new_name) < 0
|| adjust_lnnoptrs (new, a_out, new_name) < 0