minix/commands/nm/nm.c
2010-05-12 16:28:54 +00:00

226 lines
5.1 KiB
C

/* nm - print name list. Author: Dick van Veen */
/* Dick van Veen: veench@cs.vu.nl */
#include <sys/types.h>
#include <a.out.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
/* Read the name list in memory, sort it, and print it. */
/* Nm [-gnopru] [file] ...
*
* flags:
* -d address in decimal
* -g print only external symbols.
* -n sort numerically rather than alphabetically.
* -o prepend file name to each line rather than only once.
* -p don't sort, pint n symbol-table order.
* -r sort in reverse order.
* -u print only undefined symbols.
*
* - when no file name is present, a.out is assumed.
*
* NOTE: no archives are supported because assembly files don't
* have symbol tables.
*
*/
#define A_OUT "a.out"
int d_flag;
int g_flag;
int n_flag;
int o_flag;
int p_flag;
int r_flag;
int u_flag;
char io_buf[BUFSIZ]; /* io buffer */
struct exec header; /* header of a.out file */
int stbl_elems; /* #elements in symbol table */
_PROTOTYPE(int main, (int argc, char **argv));
_PROTOTYPE(int nm_sort, (const void *tmp_stbl1, const void *tmp_stbl2));
_PROTOTYPE(void nm, (char *file));
_PROTOTYPE(int read_header, (int fd));
_PROTOTYPE(void nm_print, (char *file, struct nlist *stbl));
int main(argc, argv)
int argc;
char **argv;
{
argv++;
while (*argv != 0 && **argv == '-') {
*argv += 1;
while (**argv != '\0') {
switch (**argv) {
case 'd': d_flag = 1; break;
case 'g': g_flag = 1; break;
case 'n': n_flag = 1; break;
case 'o': o_flag = 1; break;
case 'p': p_flag = 1; break;
case 'r': r_flag = 1; break;
case 'u': u_flag = 1; break;
default:
fprintf(stderr, "illegal flag: -%c\n", **argv);
exit(-1);
}
*argv += 1;
}
argv++;
}
setbuf(stdin, io_buf);
if (*argv == 0)
nm(A_OUT);
else
while (*argv != 0) {
nm(*argv);
argv++;
}
return(0);
}
int nm_sort(tmp_stbl1, tmp_stbl2)
_CONST void *tmp_stbl1, *tmp_stbl2;
{
struct nlist *stbl1 = (struct nlist *)tmp_stbl1;
struct nlist *stbl2 = (struct nlist *)tmp_stbl2;
int cmp;
if (n_flag) { /* sort numerically */
if ((stbl1->n_sclass & N_SECT) <
(stbl2->n_sclass & N_SECT))
cmp = -1;
else if ((stbl1->n_sclass & N_SECT) >
(stbl2->n_sclass & N_SECT))
cmp = 1;
else if (stbl1->n_value < stbl2->n_value)
cmp = -1;
else if (stbl1->n_value > stbl2->n_value)
cmp = 1;
else
cmp = strncmp(stbl1->n_name, stbl2->n_name, (size_t)8);
} else {
cmp = strncmp(stbl1->n_name, stbl2->n_name, (size_t)8);
if (cmp == 0) {
if (stbl1->n_value < stbl2->n_value)
cmp = -1;
else if (stbl1->n_value > stbl2->n_value)
cmp = 1;
}
}
if (r_flag) cmp = -cmp; /* reverse sort */
return(cmp);
}
void nm(file)
char *file;
{
struct nlist *stbl;
int fd;
fd = open(file, O_RDONLY);
if (fd == -1) {
fprintf(stderr, "can't open %s\n", file);
return;
}
if (read_header(fd)) {
fprintf(stderr, "%s: no executable file\n", file);
close(fd);
return;
}
if (header.a_syms == 0) {
close(fd);
return;
}
if ((size_t) header.a_syms != header.a_syms) {
fprintf(stderr, "%s: symbol table too large to allocate\n", file);
close(fd);
return;
}
if ((int) header.a_syms != header.a_syms) {
/* This is necessary because we are too lazy to iterate the read. */
fprintf(stderr, "%s: symbol table too large to read\n", file);
close(fd);
return;
}
stbl = (struct nlist *) malloc((size_t) header.a_syms);
if (stbl == NULL) {
fprintf(stderr, "%s: can't allocate symbol table\n", file);
close(fd);
return;
}
if (read(fd, (char *) stbl, (unsigned) header.a_syms) != header.a_syms) {
fprintf(stderr, "%s: can't read symbol table\n", file);
free(stbl);
close(fd);
return;
}
stbl_elems = (int) header.a_syms / sizeof(struct nlist);
if (!p_flag) qsort(stbl, (size_t)stbl_elems, sizeof(struct nlist), nm_sort);
nm_print(file, stbl);
free(stbl);
close(fd);
}
int read_header(fd)
int fd;
{
if (read(fd, (char *) &header, sizeof(struct exec)) != sizeof(struct exec))
return(1);
if (BADMAG(header)) return(1);
lseek(fd, A_SYMPOS(header), SEEK_SET);
return(0);
}
void nm_print(file, stbl)
char *file;
register struct nlist *stbl;
{
struct nlist *last;
char name[9];
int n_sclass;
char type;
name[8] = '\0';
if (!o_flag) printf("%s:\n", file);
for (last = &stbl[stbl_elems]; stbl != last; stbl++) {
if (g_flag && (stbl->n_sclass & N_CLASS) != C_EXT) continue;
if (u_flag && (stbl->n_sclass & N_SECT) != N_UNDF) continue;
n_sclass = stbl->n_sclass & N_SECT;
if (n_sclass == N_ABS)
type = 'a';
else if (n_sclass == N_TEXT)
type = 't';
else if (n_sclass == N_DATA)
type = 'd';
else if (n_sclass == N_BSS)
type = 'b';
else
type = 'u';
if ((stbl->n_sclass & N_CLASS) == C_EXT) type += 'A' - 'a';
strncpy(name, stbl->n_name, (size_t)8);
if (d_flag) {
/* Offsets in decimal. */
if (o_flag)
printf("%s:%08ld %c %s\n",file,stbl->n_value,type,name);
else
printf("%08ld %c %s\n", stbl->n_value, type, name);
} else {
/* Offsets in hex. */
if (o_flag)
printf("%s:%08lx %c %s\n",file,stbl->n_value,type,name);
else
printf("%08lx %c %s\n", stbl->n_value, type, name);
}
}
}