From ec0d22fe1571508c08b714715cfdb6ac60c53f78 Mon Sep 17 00:00:00 2001 From: "Matthias St. Pierre" Date: Wed, 25 Oct 2023 11:05:58 +0200 Subject: [PATCH] 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 Reviewed-by: Tomas Mraz (Merged from https://github.com/openssl/openssl/pull/22511) --- apps/rehash.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/apps/rehash.c b/apps/rehash.c index dbd1389acd..1e5cf38a7f 100644 --- a/apps/rehash.c +++ b/apps/rehash.c @@ -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", -- 2.34.1