I have one subtle issue on my RPM/POPT todo list since a longer
time: POPT's use of the ancient 32V AT&T UNIX alloca(3), a machine-,
compiler-, and system-dependent and especially non-POSIX (and hence
less portable) function whose use is even discouraged on lots of Unix
platforms.
POPT even uses it in a IMHO unecessary way to allocate temporary
structures on the stack:
poptDone done = alloca(sizeof(*done));
This can be just replaced by the following and let the compiler do
mostly all the work already under compile-time:
struct poptDone_s done_buf;
poptDone done = &done_buf;
The following patch completely kicks out all alloca(3) usages from POPT.
Either through the above replacement, or by not requiring a temporary
buffer at all (by passing length argument to internal findOption()
function) or in the worst cases by replacing with the POSIX malloc(3)
and calloc(3) functions.
I carefully performed the replacements, reviewed them individually and
the POPT "make check" still works, of course.
Any objections?
Ralf S. Engelschall
[EMAIL PROTECTED]
www.engelschall.com
Index: configure.ac
===================================================================
RCS file: /v/rpm/cvs/popt/configure.ac,v
retrieving revision 1.15
diff -u -d -u -d -r1.15 configure.ac
--- configure.ac 14 Jun 2007 06:42:07 -0000 1.15
+++ configure.ac 14 Jun 2007 11:38:45 -0000
@@ -67,7 +67,7 @@
fi
AC_SUBST(MARK64)
-AC_CHECK_HEADERS(alloca.h float.h libintl.h mcheck.h unistd.h)
+AC_CHECK_HEADERS(float.h libintl.h mcheck.h unistd.h)
# For some systems we know that we have ld_version scripts.
# Use it then as default.
Index: findme.c
===================================================================
RCS file: /v/rpm/cvs/popt/findme.c,v
retrieving revision 1.16
diff -u -d -u -d -r1.16 findme.c
--- findme.c 14 Jun 2007 08:22:43 -0000 1.16
+++ findme.c 14 Jun 2007 11:38:45 -0000
@@ -12,9 +12,9 @@
const char * POPT_findProgramPath(const char * argv0)
{
char * path = getenv("PATH");
- char * pathbuf;
+ char * pathbuf = NULL;
char * start, * chptr;
- char * buf;
+ char * buf = NULL;
if (argv0 == NULL) return NULL; /* XXX can't happen */
/* If there is a / in the argv[0], it has to be an absolute path */
@@ -23,9 +23,10 @@
if (path == NULL) return NULL;
- start = pathbuf = alloca(strlen(path) + 1);
+ start = pathbuf = malloc(strlen(path) + 1);
+ if (pathbuf == NULL) goto exit;
buf = malloc(strlen(path) + strlen(argv0) + sizeof("/"));
- if (buf == NULL) return NULL; /* XXX can't happen */
+ if (buf == NULL) goto exit;
strcpy(pathbuf, path);
chptr = NULL;
@@ -35,8 +36,10 @@
*chptr = '\0';
sprintf(buf, "%s/%s", start, argv0);
- if (!access(buf, X_OK))
+ if (!access(buf, X_OK)) {
+ free(pathbuf);
return buf;
+ }
if (chptr)
start = chptr + 1;
@@ -45,7 +48,11 @@
} while (start && *start);
/[EMAIL PROTECTED]@*/
- free(buf);
+exit:
+ if (pathbuf)
+ free(pathbuf);
+ if (buf)
+ free(buf);
return NULL;
}
Index: popt.c
===================================================================
RCS file: /v/rpm/cvs/popt/popt.c,v
retrieving revision 1.100
diff -u -d -u -d -r1.100 popt.c
--- popt.c 14 Jun 2007 08:22:43 -0000 1.100
+++ popt.c 14 Jun 2007 11:38:45 -0000
@@ -394,8 +394,9 @@
if (argv == NULL) return POPT_ERROR_MALLOC;
if (!strchr(item->argv[0], '/') && con->execPath != NULL) {
- char *s = alloca(strlen(con->execPath) + strlen(item->argv[0]) +
sizeof("/"));
- sprintf(s, "%s/%s", con->execPath, item->argv[0]);
+ char *s = malloc(strlen(con->execPath) + strlen(item->argv[0]) +
sizeof("/"));
+ if (s)
+ sprintf(s, "%s/%s", con->execPath, item->argv[-1]);
argv[argc] = s;
} else
argv[argc] = POPT_findProgramPath(item->argv[0]);
@@ -448,11 +449,6 @@
#endif
#endif
- if (argv[0] == NULL) {
- ec = POPT_ERROR_NOARG;
- goto exit;
- }
-
#ifdef MYDEBUG
if (_popt_debug)
{ const char ** avp;
@@ -466,14 +462,18 @@
rc = execvp(argv[0], (char *const *)argv);
exit:
- if (argv) free(argv);
+ if (argv) {
+ if (argv[0])
+ free((void *)argv[0]);
+ free(argv);
+ }
return ec;
}
/[EMAIL PROTECTED] =boundswrite @*/
/[EMAIL PROTECTED]@*/
/[EMAIL PROTECTED]@*/ /[EMAIL PROTECTED]@*/ static const struct poptOption *
-findOption(const struct poptOption * opt, /[EMAIL PROTECTED]@*/ const char *
longName,
+findOption(const struct poptOption * opt, /[EMAIL PROTECTED]@*/ const char *
longName, int longNameLen,
char shortName,
/[EMAIL PROTECTED]@*/ /[EMAIL PROTECTED]@*/ poptCallbackType *
callback,
/[EMAIL PROTECTED]@*/ /[EMAIL PROTECTED]@*/ const void **
callbackData,
@@ -498,7 +498,7 @@
/[EMAIL PROTECTED]@*/
/* Recurse on included sub-tables. */
if (arg == NULL) continue; /* XXX program error */
- opt2 = findOption(arg, longName, shortName, callback,
+ opt2 = findOption(arg, longName, longNameLen, shortName, callback,
callbackData, singleDash);
if (opt2 == NULL) continue;
/* Sub-table data will be inheirited if no data yet. */
@@ -512,7 +512,7 @@
cb = opt;
} else if (longName != NULL && opt->longName != NULL &&
(!singleDash || (opt->argInfo & POPT_ARGFLAG_ONEDASH)) &&
- !strcmp(longName, opt->longName))
+ (!strncmp(longName, opt->longName, longNameLen) &&
strlen(opt->longName) == longNameLen))
{
break;
} else if (shortName && shortName == opt->shortName) {
@@ -764,7 +764,8 @@
/* Process next long option */
if (!con->os->nextCharArg) {
- char * localOptString, * optString;
+ char * optString;
+ int optStringLen;
int thisopt;
/[EMAIL PROTECTED]@*/
@@ -795,8 +796,7 @@
}
/* Make a copy we can hack at */
- localOptString = optString =
- strcpy(alloca(strlen(origOptString) + 1), origOptString);
+ optString = origOptString;
if (optString[0] == '\0')
return POPT_ERROR_BADOPT;
@@ -824,13 +824,11 @@
/* Check for "--long=arg" option. */
for (oe = optString; *oe && *oe != '='; oe++)
{};
- if (*oe == '=') {
- *oe++ = '\0';
- /* XXX longArg is mapped back to persistent storage. */
- longArg = origOptString + (oe - localOptString);
- }
+ optStringLen = oe - optString;
+ if (*oe == '=')
+ longArg = oe + 1;
- opt = findOption(con->options, optString, '\0', &cb, &cbData,
+ opt = findOption(con->options, optString, optStringLen, '\0',
&cb, &cbData,
singleDash);
if (!opt && !singleDash)
return POPT_ERROR_BADOPT;
@@ -867,7 +865,7 @@
continue;
}
- opt = findOption(con->options, NULL, *origOptString, &cb,
+ opt = findOption(con->options, NULL, 0, *origOptString, &cb,
&cbData, 0);
if (!opt)
return POPT_ERROR_BADOPT;
@@ -1140,7 +1138,8 @@
int poptAddAlias(poptContext con, struct poptAlias alias,
/[EMAIL PROTECTED]@*/ int flags)
{
- poptItem item = alloca(sizeof(*item));
+ struct poptItem_s item_buf;
+ poptItem item = &item_buf;
memset(item, 0, sizeof(*item));
item->option.longName = alias.longName;
item->option.shortName = alias.shortName;
Index: poptconfig.c
===================================================================
RCS file: /v/rpm/cvs/popt/poptconfig.c,v
retrieving revision 1.27
diff -u -d -u -d -r1.27 poptconfig.c
--- poptconfig.c 25 May 2007 17:36:23 -0000 1.27
+++ poptconfig.c 14 Jun 2007 11:38:45 -0000
@@ -17,7 +17,8 @@
size_t nameLength;
const char * entryType;
const char * opt;
- poptItem item = alloca(sizeof(*item));
+ struct poptItem_s item_buf;
+ poptItem item = &item_buf;
int i, j;
if (con->appName == NULL)
@@ -95,8 +96,8 @@
int poptReadConfigFile(poptContext con, const char * fn)
{
- const char * file, * chptr, * end;
- char * buf;
+ char * file = NULL, * chptr, * end;
+ char * buf = NULL;
/[EMAIL PROTECTED]@*/ char * dst;
int fd, rc;
off_t fileLength;
@@ -113,18 +114,20 @@
return POPT_ERROR_ERRNO;
}
- file = alloca(fileLength + 1);
+ file = malloc(fileLength + 1);
if (read(fd, (char *)file, fileLength) != fileLength) {
rc = errno;
(void) close(fd);
errno = rc;
return POPT_ERROR_ERRNO;
}
- if (close(fd) == -1)
+ if (close(fd) == -1) {
+ free(file);
return POPT_ERROR_ERRNO;
+ }
/[EMAIL PROTECTED]@*/
- dst = buf = alloca(fileLength + 1);
+ dst = buf = malloc(fileLength + 1);
chptr = file;
end = (file + fileLength);
@@ -157,6 +160,9 @@
/[EMAIL PROTECTED]@*/
/[EMAIL PROTECTED]@*/
+ free(file);
+ free(buf);
+
return 0;
}
@@ -171,10 +177,11 @@
if (rc) return rc;
if ((home = getenv("HOME"))) {
- fn = alloca(strlen(home) + 20);
+ fn = malloc(strlen(home) + 20);
strcpy(fn, home);
strcat(fn, "/.popt");
rc = poptReadConfigFile(con, fn);
+ free(fn);
if (rc) return rc;
}
Index: popthelp.c
===================================================================
RCS file: /v/rpm/cvs/popt/popthelp.c,v
retrieving revision 1.56
diff -u -d -u -d -r1.56 popthelp.c
--- popthelp.c 14 Jun 2007 08:08:30 -0000 1.56
+++ popthelp.c 14 Jun 2007 11:38:45 -0000
@@ -767,11 +767,14 @@
/[EMAIL PROTECTED] *str, *fp, fileSystem @*/
/[EMAIL PROTECTED] maxRead(str) >= 0 @*/
{
- /* bufsize larger then the ascii set, lazy alloca on top level call. */
+ /* bufsize larger then the ascii set, lazy allocation on top level call. */
size_t nb = (size_t)300;
- char * s = (str != NULL ? str : memset(alloca(nb), 0, nb));
+ char * s = (str != NULL ? str : calloc(1, nb));
size_t len = (size_t)0;
+ if (s == NULL)
+ return 0;
+
/[EMAIL PROTECTED]@*/
if (opt != NULL)
for (; (opt->longName || opt->shortName || opt->arg); opt++) {
@@ -788,19 +791,23 @@
fprintf(fp, " [-%s]", s);
len = strlen(s) + sizeof(" [-]")-1;
}
+ if (s != str)
+ free(s);
return len;
}
void poptPrintUsage(poptContext con, FILE * fp, /[EMAIL PROTECTED]@*/ int
flags)
{
- poptDone done = memset(alloca(sizeof(*done)), 0, sizeof(*done));
+ struct poptDone_s done_buf;
+ poptDone done = &done_buf;
size_t cursor;
+ memset(done, 0, sizeof(*done));
done->nopts = 0;
done->maxopts = 64;
cursor = done->maxopts * sizeof(*done->opts);
/[EMAIL PROTECTED]@*/
- done->opts = memset(alloca(cursor), 0, cursor);
+ done->opts = calloc(1, cursor);
/[EMAIL PROTECTED]@*/
done->opts[done->nopts++] = (const void *) con->options;
/[EMAIL PROTECTED]@*/
@@ -819,6 +826,7 @@
}
fprintf(fp, "\n");
+ free(done->opts);
}
void poptSetOtherOptionHelp(poptContext con, const char * text)
Index: poptparse.c
===================================================================
RCS file: /v/rpm/cvs/popt/poptparse.c,v
retrieving revision 1.22
diff -u -d -u -d -r1.22 poptparse.c
--- poptparse.c 14 Jun 2007 08:04:38 -0000 1.22
+++ poptparse.c 14 Jun 2007 11:38:45 -0000
@@ -62,10 +62,12 @@
const char ** argv = malloc(sizeof(*argv) * argvAlloced);
int argc = 0;
size_t buflen = strlen(s) + 1;
- char * buf = memset(alloca(buflen), 0, buflen);
+ char * buf, * bufOrig = NULL;
int rc = POPT_ERROR_MALLOC;
if (argv == NULL) return rc;
+ buf = bufOrig = calloc(1, buflen);
+ if (buf == NULL) return rc;
argv[argc] = buf;
for (src = s; *src != '\0'; src++) {
@@ -116,6 +118,7 @@
rc = poptDupArgv(argc, argv, argcPtr, argvPtr);
exit:
+ if (bufOrig) free(bufOrig);
if (argv) free(argv);
return rc;
}
Index: system.h
===================================================================
RCS file: /v/rpm/cvs/popt/system.h,v
retrieving revision 1.9
diff -u -d -u -d -r1.9 system.h
--- system.h 14 Jun 2007 08:16:01 -0000 1.9
+++ system.h 14 Jun 2007 11:38:45 -0000
@@ -39,32 +39,6 @@
#include <libc.h>
#endif
-#if defined(__LCLINT__)
-/[EMAIL PROTECTED] -incondefs @*/ /* LCL: missing annotation */
-/[EMAIL PROTECTED]@*/ /[EMAIL PROTECTED]@*/
-void * alloca (size_t __size)
- /[EMAIL PROTECTED] MaxSet(result) == (__size - 1) @*/
- /[EMAIL PROTECTED]/;
-/[EMAIL PROTECTED] =incondefs @*/
-#endif
-
-/* AIX requires this to be the first thing in the file. */
-#ifndef __GNUC__
-# ifdef HAVE_ALLOCA_H
-# include <alloca.h>
-# else
-# ifdef _AIX
-#pragma alloca
-# else
-# ifndef alloca /* predefined by HP cc +Olibcalls */
-char *alloca ();
-# endif
-# endif
-# endif
-#elif defined(__GNUC__) && defined(__STRICT_ANSI__)
-#define alloca __builtin_alloca
-#endif
-
/[EMAIL PROTECTED] [EMAIL PROTECTED]/
/[EMAIL PROTECTED]@*/ /[EMAIL PROTECTED]@*/ /[EMAIL PROTECTED]@*/
char * xstrdup (const char *str)
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