[PATCH 06/10] global: fix unsigned integer promotions in ternary statements
- From
Patrick Steinhardt <ps@pks.im>
- Date
- Nov 29, 2024, 13:13 UTC
- Message-ID
- <20241129-pks-sign-compare-v1-6-fc406b984bc9@pks.im>
- In-Reply-To
- <20241129-pks-sign-compare-v1-0-fc406b984bc9@pks.im>
We have several cases in our codebase where the ternary operator changes signedness from a signed integer type to an unsigned one. This causes warnings with `-Wsign-compare`. Generally, we seem to have three classes of this in our codebase:
- Cases where we know that the result is well-formed, e.g. when
indexing into strings to determine the length of substrings. - Cases where we want `-1` to mean "unlimited", counting on the
wrap-around. - Cases where we may indeed run into problems when one of the
statements returns a value that is too big.Out of these only the last class is a bit worrying, but we can address it by adding a call to `cast_size_t_to_int()`. Like this we're better protected in case we have unexpectedly huge input as we'd die instead of silently doing the wrong thing.
Signed-off-by: Patrick Steinhardt <ps@pks.im> --- builtin/blame.c | 3 ++- builtin/patch-id.c | 2 +- dir.c | 4 ++-- gettext.c | 4 +--- gpg-interface.c | 2 +- scalar.c | 2 +- strbuf.c | 2 +- t/helper/test-csprng.c | 4 +--- t/helper/test-genrandom.c | 4 +--- 9 files changed, 11 insertions(+), 16 deletions(-)
diff --git a/builtin/blame.c b/builtin/blame.c index f0d209791e44025b1965cd447cf4fc1e2ca5f009..6c6b0c7ef1a4d992064c7664bbf1229ef0286b97 100644 --- a/builtin/blame.c +++ b/builtin/blame.c @@ -470,7 +470,8 @@ static void emit_other(struct blame_scoreboard *sb, struct blame_entry *ent, int for (cnt = 0; cnt < ent->num_lines; cnt++) { char ch; - int length = (opt & OUTPUT_LONG_OBJECT_NAME) ? the_hash_algo->hexsz : abbrev; + int length = (opt & OUTPUT_LONG_OBJECT_NAME) ? + cast_size_t_to_int(the_hash_algo->hexsz) : abbrev; if (opt & OUTPUT_COLOR_LINE) { if (cnt > 0) { diff --git a/builtin/patch-id.c b/builtin/patch-id.c index 56585757477911c96bbb9ef2cf3710691b8e744e..87fa586c4d552ba61cd2ac2cf079d68241eb3275 100644 --- a/builtin/patch-id.c +++ b/builtin/patch-id.c @@ -163,7 +163,7 @@ static int get_one_patchid(struct object_id *next_oid, struct object_id *result, after--; /* Add line to hash algo (possibly removing whitespace) */ - len = verbatim ? strlen(line) : remove_space(line); + len = verbatim ? cast_size_t_to_int(strlen(line)) : remove_space(line); patchlen += len; the_hash_algo->update_fn(&ctx, line, len); } diff --git a/dir.c b/dir.c index 5b2181e5899ce951791aa5e46ccdbb2d71ce6144..fc77ffe56c9d8353d918553223f5521fa3bc3a94 100644 --- a/dir.c +++ b/dir.c @@ -1643,7 +1643,7 @@ static void prep_exclude(struct dir_struct *dir, strbuf_init(&dir->internal.basebuf, PATH_MAX); /* Read from the parent directories and push them down. */ - current = stk ? stk->baselen : -1; + current = stk ? cast_size_t_to_int(stk->baselen) : -1; strbuf_setlen(&dir->internal.basebuf, current < 0 ? 0 : current); if (dir->untracked) untracked = stk ? stk->ucd : dir->untracked->root; @@ -2896,7 +2896,7 @@ static void new_untracked_cache(struct index_state *istate, int flags) struct untracked_cache *uc = xcalloc(1, sizeof(*uc)); strbuf_init(&uc->ident, 100); uc->exclude_per_dir = ".gitignore"; - uc->dir_flags = flags >= 0 ? flags : new_untracked_cache_flags(istate); + uc->dir_flags = flags >= 0 ? (unsigned) flags : new_untracked_cache_flags(istate); set_untracked_ident(uc); istate->untracked = uc; istate->cache_changed |= UNTRACKED_CHANGED; diff --git a/gettext.c b/gettext.c index 8d08a61f8487dc30559e5e5d6d31cf06a92789e1..ecb0c70c1144ce8b4280b78a2b443138e8af6603 100644 --- a/gettext.c +++ b/gettext.c @@ -2,8 +2,6 @@ * Copyright (c) 2010 Ævar Arnfjörð Bjarmason */ -#define DISABLE_SIGN_COMPARE_WARNINGS - #include "git-compat-util.h" #include "abspath.h" #include "environment.h" @@ -135,7 +133,7 @@ int gettext_width(const char *s) if (is_utf8 == -1) is_utf8 = is_utf8_locale(); - return is_utf8 ? utf8_strwidth(s) : strlen(s); + return is_utf8 ? utf8_strwidth(s) : cast_size_t_to_int(strlen(s)); } #endif diff --git a/gpg-interface.c b/gpg-interface.c index a67d80475bf9d8452de0c3ae9bb08ceeb4c11c4b..e1720361f17e8b3b3315f0a5d93a827e11b2b036 100644 --- a/gpg-interface.c +++ b/gpg-interface.c @@ -700,7 +700,7 @@ size_t parse_signed_buffer(const char *buf, size_t size) match = len; eol = memchr(buf + len, '\n', size - len); - len += eol ? eol - (buf + len) + 1 : size - len; + len += eol ? (size_t) (eol - (buf + len) + 1) : size - len; } return match; } diff --git a/scalar.c b/scalar.c index 87bb30991bf768534a988608d9b194dc8b5ba78a..ce18fab07c08be715142379fd9d757e96c554fbb 100644 --- a/scalar.c +++ b/scalar.c @@ -380,7 +380,7 @@ static int delete_enlistment(struct strbuf *enlistment) offset = offset_1st_component(enlistment->buf); path_sep = find_last_dir_sep(enlistment->buf + offset); strbuf_add(&parent, enlistment->buf, - path_sep ? path_sep - enlistment->buf : offset); + path_sep ? (size_t) (path_sep - enlistment->buf) : offset); if (chdir(parent.buf) < 0) { int res = error_errno(_("could not switch to '%s'"), parent.buf); strbuf_release(&parent); diff --git a/strbuf.c b/strbuf.c index 8ddd4b06c595ac3f8b38a65d3e1ca4b340fddf9f..8c027a67942a72b9078c7f6e144c883c76d461d4 100644 --- a/strbuf.c +++ b/strbuf.c @@ -1055,7 +1055,7 @@ void strbuf_stripspace(struct strbuf *sb, const char *comment_prefix) for (i = j = 0; i < sb->len; i += len, j += newlen) { eol = memchr(sb->buf + i, '\n', sb->len - i); - len = eol ? eol - (sb->buf + i) + 1 : sb->len - i; + len = eol ? (size_t) (eol - (sb->buf + i) + 1) : sb->len - i; if (comment_prefix && len && starts_with(sb->buf + i, comment_prefix)) { diff --git a/t/helper/test-csprng.c b/t/helper/test-csprng.c index ea9b9b656307d32bdc1f2e15a91793b1dda9c463..31dbe7db4ac61639541f15d262cea64368fec78f 100644 --- a/t/helper/test-csprng.c +++ b/t/helper/test-csprng.c @@ -1,5 +1,3 @@ -#define DISABLE_SIGN_COMPARE_WARNINGS - #include "test-tool.h" #include "git-compat-util.h" @@ -14,7 +12,7 @@ int cmd__csprng(int argc, const char **argv) return 2; } - count = (argc == 2) ? strtoul(argv[1], NULL, 0) : -1L; + count = (argc == 2) ? strtoul(argv[1], NULL, 0) : (unsigned long) -1L; while (count) { unsigned long chunk = count < sizeof(buf) ? count : sizeof(buf); diff --git a/t/helper/test-genrandom.c b/t/helper/test-genrandom.c index 5b51e6648d8e698b09f400efcf67a0708c226e9d..efca20e7efff46bf66c2b8888ce88db02e545cd5 100644 --- a/t/helper/test-genrandom.c +++ b/t/helper/test-genrandom.c @@ -4,8 +4,6 @@ * Copyright (C) 2007 by Nicolas Pitre, licensed under the GPL version 2. */ -#define DISABLE_SIGN_COMPARE_WARNINGS - #include "test-tool.h" #include "git-compat-util.h" @@ -24,7 +22,7 @@ int cmd__genrandom(int argc, const char **argv) next = next * 11 + *c; } while (*c++); - count = (argc == 3) ? strtoul(argv[2], NULL, 0) : -1L; + count = (argc == 3) ? strtoul(argv[2], NULL, 0) : (unsigned long) -1L; while (count--) { next = next * 1103515245 + 12345;
-- 2.47.0.366.g5daf58cba8.dirty