in dso/aix/dso.c [501:666]
static int readExports(ModulePtr mp)
{
LDFILE *ldp = NULL;
SCNHDR sh, shdata;
LDHDR *lhp;
char *ldbuf;
LDSYM *ls;
int i;
ExportPtr ep;
struct ld_info *lp;
char *buf;
int size = 4 * 1024;
void *dataorg;
/*
* The module might be loaded due to the LIBPATH
* environment variable. Search for the loaded
* module using L_GETINFO.
*/
if ((buf = malloc(size)) == NULL) {
errvalid++;
strcpy(errbuf, "readExports: ");
strcat(errbuf, strerror(errno));
return -1;
}
while ((i = loadquery(L_GETINFO, buf, size)) == -1 && errno == ENOMEM) {
free(buf);
size += 4 * 1024;
if ((buf = malloc(size)) == NULL) {
errvalid++;
strcpy(errbuf, "readExports: ");
strcat(errbuf, strerror(errno));
return -1;
}
}
if (i == -1) {
errvalid++;
strcpy(errbuf, "readExports: ");
strcat(errbuf, strerror(errno));
free(buf);
return -1;
}
/*
* Traverse the list of loaded modules. The entry point
* returned by load() does actually point to the TOC
* entry contained in the data segment.
*/
lp = (struct ld_info *) buf;
while (lp) {
if ((unsigned long) mp->entry >= (unsigned long) lp->ldinfo_dataorg &&
(unsigned long) mp->entry < (unsigned long) lp->ldinfo_dataorg +
lp->ldinfo_datasize) {
dataorg = lp->ldinfo_dataorg;
ldp = ldopen(lp->ldinfo_filename, ldp);
break;
}
if (lp->ldinfo_next == 0)
lp = NULL;
else
lp = (struct ld_info *) ((char *) lp + lp->ldinfo_next);
}
free(buf);
if (!ldp) {
errvalid++;
strcpy(errbuf, "readExports: ");
strcat(errbuf, strerror(errno));
return -1;
}
if (TYPE(ldp) != U802TOCMAGIC) {
errvalid++;
strcpy(errbuf, "readExports: bad magic");
while (ldclose(ldp) == FAILURE);
return -1;
}
/*
* Get the padding for the data section. This is needed for
* AIX 4.1 compilers. This is used when building the final
* function pointer to the exported symbol.
*/
if (ldnshread(ldp, _DATA, &shdata) != SUCCESS) {
errvalid++;
strcpy(errbuf, "readExports: cannot read data section header");
while (ldclose(ldp) == FAILURE);
return -1;
}
if (ldnshread(ldp, _LOADER, &sh) != SUCCESS) {
errvalid++;
strcpy(errbuf, "readExports: cannot read loader section header");
while (ldclose(ldp) == FAILURE);
return -1;
}
/*
* We read the complete loader section in one chunk, this makes
* finding long symbol names residing in the string table easier.
*/
if ((ldbuf = (char *) malloc(sh.s_size)) == NULL) {
errvalid++;
strcpy(errbuf, "readExports: ");
strcat(errbuf, strerror(errno));
while (ldclose(ldp) == FAILURE);
return -1;
}
if (FSEEK(ldp, sh.s_scnptr, BEGINNING) != OKFSEEK) {
errvalid++;
strcpy(errbuf, "readExports: cannot seek to loader section");
free(ldbuf);
while (ldclose(ldp) == FAILURE);
return -1;
}
if (FREAD(ldbuf, sh.s_size, 1, ldp) != 1) {
errvalid++;
strcpy(errbuf, "readExports: cannot read loader section");
free(ldbuf);
while (ldclose(ldp) == FAILURE);
return -1;
}
lhp = (LDHDR *) ldbuf;
ls = (LDSYM *) (ldbuf + LDHDRSZ);
/*
* Count the number of exports to include in our export table.
*/
for (i = lhp->l_nsyms; i; i--, ls++) {
if (!LDR_EXPORT(*ls))
continue;
mp->nExports++;
}
if ((mp->exports = (ExportPtr) calloc(mp->nExports, sizeof(*mp->exports))) == NULL) {
errvalid++;
strcpy(errbuf, "readExports: ");
strcat(errbuf, strerror(errno));
free(ldbuf);
while (ldclose(ldp) == FAILURE);
return -1;
}
/*
* Fill in the export table. All entries are relative to
* the beginning of the data origin.
*/
ep = mp->exports;
ls = (LDSYM *) (ldbuf + LDHDRSZ);
for (i = lhp->l_nsyms; i; i--, ls++) {
char *symname;
char tmpsym[SYMNMLEN + 1];
if (!LDR_EXPORT(*ls))
continue;
if (ls->l_zeroes == 0)
symname = ls->l_offset + lhp->l_stoff + ldbuf;
else {
/*
* The l_name member is not zero terminated, we
* must copy the first SYMNMLEN chars and make
* sure we have a zero byte at the end.
*/
strncpy(tmpsym, ls->l_name, SYMNMLEN);
tmpsym[SYMNMLEN] = '\0';
symname = tmpsym;
}
ep->name = strdup(symname);
ep->addr = (void *) ((unsigned long) dataorg +
ls->l_value - shdata.s_vaddr);
ep++;
}
free(ldbuf);
while (ldclose(ldp) == FAILURE);
return 0;
}