apps/rehash.c: avoid printf format warning [-Wformat]

The `aarch64-linux-android33-clang` cross-compiler (v14.0.6)
complains twice about an unsupported '%n' format specifier,
preventing a successful `--strict-warnings` build:

    error: '%n' specifier not supported on this platform [-Werror,-Wformat]
                BIO_snprintf(buf, buflen, "%s%s%n%08x.%s%d",

This is a false positive, because BIO_snprintf() implements its
own format parsing (which is implemented in the _dopr() function).

This commit fixes the problem by rewriting the code to dispense with
the dubious '%n' format specifier. As a side-effect, the code becomes
a little bit more comprehensible and self-explaining.

Reviewed-by: David von Oheimb <david.von.oheimb@siemens.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/22511)
This commit is contained in:
Matthias St. Pierre 2023-10-25 11:05:58 +02:00 committed by Tomas Mraz
parent 7cf75e5caa
commit ec0d22fe15
1 changed files with 14 additions and 11 deletions

View File

@ -355,9 +355,9 @@ static int do_dir(const char *dirname, enum Hash h)
OPENSSL_DIR_CTX *d = NULL;
struct stat st;
unsigned char idmask[MAX_COLLISIONS / 8];
int n, numfiles, nextid, buflen, errs = 0;
int n, numfiles, nextid, dirlen, buflen, errs = 0;
size_t i;
const char *pathsep;
const char *pathsep = "";
const char *filename;
char *buf, *copy = NULL;
STACK_OF(OPENSSL_STRING) *files = NULL;
@ -366,9 +366,12 @@ static int do_dir(const char *dirname, enum Hash h)
BIO_printf(bio_err, "Skipping %s, can't write\n", dirname);
return 1;
}
buflen = strlen(dirname);
pathsep = (buflen && !ends_with_dirsep(dirname)) ? "/": "";
buflen += NAME_MAX + 1 + 1;
dirlen = strlen(dirname);
if (dirlen != 0 && !ends_with_dirsep(dirname)) {
pathsep = "/";
dirlen++;
}
buflen = dirlen + NAME_MAX + 1;
buf = app_malloc(buflen, "filename buffer");
if (verbose)
@ -427,12 +430,12 @@ static int do_dir(const char *dirname, enum Hash h)
while (bit_isset(idmask, nextid))
nextid++;
BIO_snprintf(buf, buflen, "%s%s%n%08x.%s%d",
dirname, pathsep, &n, bp->hash,
BIO_snprintf(buf, buflen, "%s%s%08x.%s%d",
dirname, pathsep, bp->hash,
suffixes[bp->type], nextid);
if (verbose)
BIO_printf(bio_out, "link %s -> %s\n",
ep->filename, &buf[n]);
ep->filename, &buf[dirlen]);
if (unlink(buf) < 0 && errno != ENOENT) {
BIO_printf(bio_err,
"%s: Can't unlink %s, %s\n",
@ -449,12 +452,12 @@ static int do_dir(const char *dirname, enum Hash h)
bit_set(idmask, nextid);
} else if (remove_links) {
/* Link to be deleted */
BIO_snprintf(buf, buflen, "%s%s%n%08x.%s%d",
dirname, pathsep, &n, bp->hash,
BIO_snprintf(buf, buflen, "%s%s%08x.%s%d",
dirname, pathsep, bp->hash,
suffixes[bp->type], ep->old_id);
if (verbose)
BIO_printf(bio_out, "unlink %s\n",
&buf[n]);
&buf[dirlen]);
if (unlink(buf) < 0 && errno != ENOENT) {
BIO_printf(bio_err,
"%s: Can't unlink %s, %s\n",