Am 09.05.19 um 20:38 schrieb Jeff King:
> I do dream of a world where we do not have a bunch of implicit
> conversions (both signedness but also truncation) in our code base, and
> can compile cleanly with -Wconversion We know that this case is
> perfectly fine, but I am sure there are many that are not. However, I'm
> not sure if we'll ever get there, and in the meantime I don't think it's
> worth worrying too much about individual cases like this.
Here's a rough take on how to silence that warning for archive-tar.c using
GCC 8.3. Some of the changes are worth polishing and submitting. Some
are silly. The one for regexec_buf() is scary; I don't see a clean way of
dealing with that size_t to int conversion.
---
archive-tar.c | 54 +++++++++++++++++++++++++++++++----------------
cache.h | 10 ++++-----
git-compat-util.h | 21 +++++++++++++++---
hash.h | 2 +-
strbuf.h | 2 +-
5 files changed, 61 insertions(+), 28 deletions(-)
diff --git a/archive-tar.c b/archive-tar.c
index 3e53aac1e6..bfd91782ab 100644
--- a/archive-tar.c
+++ b/archive-tar.c
@@ -15,7 +15,7 @@
static char block[BLOCKSIZE];
static unsigned long offset;
-static int tar_umask = 002;
+static mode_t tar_umask = 002;
static int write_tar_filter_archive(const struct archiver *ar,
struct archiver_args *args);
@@ -99,7 +99,7 @@ static void write_blocked(const void *data, unsigned long
size)
*/
static void write_trailer(void)
{
- int tail = BLOCKSIZE - offset;
+ size_t tail = BLOCKSIZE - offset;
memset(block + offset, 0, tail);
write_or_die(1, block, BLOCKSIZE);
if (tail < 2 * RECORDSIZE) {
@@ -127,12 +127,13 @@ static int stream_blocked(const struct object_id *oid)
readlen = read_istream(st, buf, sizeof(buf));
if (readlen <= 0)
break;
- do_write_blocked(buf, readlen);
+ do_write_blocked(buf, (size_t)readlen);
}
close_istream(st);
- if (!readlen)
- finish_record();
- return readlen;
+ if (readlen < 0)
+ return -1;
+ finish_record();
+ return 0;
}
/*
@@ -142,9 +143,9 @@ static int stream_blocked(const struct object_id *oid)
* string and appends it to a struct strbuf.
*/
static void strbuf_append_ext_header(struct strbuf *sb, const char *keyword,
- const char *value, unsigned int valuelen)
+ const char *value, size_t valuelen)
{
- int len, tmp;
+ size_t len, tmp;
/* "%u %s=%s\n" */
len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1;
@@ -152,7 +153,7 @@ static void strbuf_append_ext_header(struct strbuf *sb,
const char *keyword,
len++;
strbuf_grow(sb, len);
- strbuf_addf(sb, "%u %s=", len, keyword);
+ strbuf_addf(sb, "%"PRIuMAX" %s=", (uintmax_t)len, keyword);
strbuf_add(sb, value, valuelen);
strbuf_addch(sb, '\n');
}
@@ -168,7 +169,9 @@ static void strbuf_append_ext_header_uint(struct strbuf *sb,
int len;
len = xsnprintf(buf, sizeof(buf), "%"PRIuMAX, value);
- strbuf_append_ext_header(sb, keyword, buf, len);
+ if (len < 0)
+ BUG("unable to convert %"PRIuMAX" to decimal", value);
+ strbuf_append_ext_header(sb, keyword, buf, (size_t)len);
}
static unsigned int ustar_header_chksum(const struct ustar_header *header)
@@ -177,7 +180,7 @@ static unsigned int ustar_header_chksum(const struct
ustar_header *header)
unsigned int chksum = 0;
while (p < (const unsigned char *)header->chksum)
chksum += *p++;
- chksum += sizeof(header->chksum) * ' ';
+ chksum += (unsigned int)sizeof(header->chksum) * ' ';
p += sizeof(header->chksum);
while (p < (const unsigned char *)header + sizeof(struct ustar_header))
chksum += *p++;
@@ -355,12 +358,14 @@ static void write_global_extended_header(struct
archiver_args *args)
}
static struct archiver **tar_filters;
-static int nr_tar_filters;
-static int alloc_tar_filters;
+static size_t nr_tar_filters;
+static size_t alloc_tar_filters;
-static struct archiver *find_tar_filter(const char *name, int len)
+static struct archiver *find_tar_filter(const char *name, size_t len)
{
int i;
+ if (len < 1)
+ return NULL;
for (i = 0; i < nr_tar_filters; i++) {
struct archiver *ar = tar_filters[i];
if (!strncmp(ar->name, name, len) && !ar->name[len])
@@ -369,14 +374,27 @@ static struct archiver *find_tar_filter(const char *name,
int len)
return NULL;
}
+static int parse_config_key2(const char *var, const char *section,
+ const char **subsection, size_t *subsection_len,
+ const char **key)
+{
+ int rc, len;
+
+ rc = parse_config_key(var, section, subsection, &len, key);
+ if (!rc && len < 0)
+ return -1;
+ *subsection_len = (size_t)len;
+ return rc;
+}
+
static int tar_filter_config(const char *var, const char *value, void *data)
{
struct archiver *ar;
const char *name;
const char *type;
- int namelen;
+ size_t namelen;
- if (parse_config_key(var, "tar", &name, &namelen, &type) < 0 || !name)
+ if (parse_config_key2(var, "tar", &name, &namelen, &type) < 0 || !name)
return 0;
ar = find_tar_filter(name, namelen);
@@ -400,7 +418,7 @@ static int tar_filter_config(const char *var, const char
*value, void *data)
if (git_config_bool(var, value))
ar->flags |= ARCHIVER_REMOTE;
else
- ar->flags &= ~ARCHIVER_REMOTE;
+ ar->flags &= ~(unsigned int)ARCHIVER_REMOTE;
return 0;
}
@@ -414,7 +432,7 @@ static int git_tar_config(const char *var, const char
*value, void *cb)
tar_umask = umask(0);
umask(tar_umask);
} else {
- tar_umask = git_config_int(var, value);
+ tar_umask = (mode_t)git_config_ulong(var, value);
}
return 0;
}
diff --git a/cache.h b/cache.h
index 67cc2e1806..a791034260 100644
--- a/cache.h
+++ b/cache.h
@@ -241,7 +241,7 @@ static inline void copy_cache_entry(struct cache_entry *dst,
const struct cache_entry *src)
{
unsigned int state = dst->ce_flags & CE_HASHED;
- int mem_pool_allocated = dst->mem_pool_allocated;
+ unsigned int mem_pool_allocated = dst->mem_pool_allocated;
/* Don't copy hash chain and name */
memcpy(&dst->ce_stat_data, &src->ce_stat_data,
@@ -249,7 +249,7 @@ static inline void copy_cache_entry(struct cache_entry *dst,
offsetof(struct cache_entry, ce_stat_data));
/* Restore the hash state */
- dst->ce_flags = (dst->ce_flags & ~CE_HASHED) | state;
+ dst->ce_flags = (dst->ce_flags & ~(unsigned int)CE_HASHED) | state;
/* Restore the mem_pool_allocated flag */
dst->mem_pool_allocated = mem_pool_allocated;
@@ -1314,7 +1314,7 @@ extern int check_and_freshen_file(const char *fn, int
freshen);
extern const signed char hexval_table[256];
static inline unsigned int hexval(unsigned char c)
{
- return hexval_table[c];
+ return (unsigned int)hexval_table[c];
}
/*
@@ -1323,8 +1323,8 @@ static inline unsigned int hexval(unsigned char c)
*/
static inline int hex2chr(const char *s)
{
- unsigned int val = hexval(s[0]);
- return (val & ~0xf) ? val : (val << 4) | hexval(s[1]);
+ int val = hexval_table[(unsigned char)s[0]];
+ return (val < 0) ? val : (val << 4) | hexval_table[(unsigned char)s[1]];
}
/* Convert to/from hex/sha1 representation */
diff --git a/git-compat-util.h b/git-compat-util.h
index 4386b3e1c8..cf33e84c96 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1068,7 +1068,7 @@ static inline int strtoul_ui(char const *s, int base,
unsigned int *result)
ul = strtoul(s, &p, base);
if (errno || *p || p == s || (unsigned int) ul != ul)
return -1;
- *result = ul;
+ *result = (unsigned int)ul;
return 0;
}
@@ -1081,7 +1081,7 @@ static inline int strtol_i(char const *s, int base, int
*result)
ul = strtol(s, &p, base);
if (errno || *p || p == s || (int) ul != ul)
return -1;
- *result = ul;
+ *result = (int)ul;
return 0;
}
@@ -1119,7 +1119,22 @@ static inline int regexec_buf(const regex_t *preg, const
char *buf, size_t size,
{
assert(nmatch > 0 && pmatch);
pmatch[0].rm_so = 0;
- pmatch[0].rm_eo = size;
+ pmatch[0].rm_eo = (regoff_t)size;
+ if (pmatch[0].rm_eo != size) {
+ if (((regoff_t)-1) < 0) {
+ if (sizeof(regoff_t) == sizeof(int))
+ pmatch[0].rm_eo = (regoff_t)INT_MAX;
+ else if (sizeof(regoff_t) == sizeof(long))
+ pmatch[0].rm_eo = (regoff_t)LONG_MAX;
+ else
+ die("unable to determine maximum value of
regoff_t");
+ } else {
+ pmatch[0].rm_eo = (regoff_t)-1;
+ }
+ warning("buffer too big (%"PRIuMAX"), "
+ "will search only the first %"PRIuMAX" bytes",
+ (uintmax_t)size, (uintmax_t)pmatch[0].rm_eo);
+ }
return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
}
diff --git a/hash.h b/hash.h
index 661c9f2281..7056f89eb4 100644
--- a/hash.h
+++ b/hash.h
@@ -134,7 +134,7 @@ int hash_algo_by_id(uint32_t format_id);
/* Identical, except based on the length. */
int hash_algo_by_length(int len);
/* Identical, except for a pointer to struct git_hash_algo. */
-static inline int hash_algo_by_ptr(const struct git_hash_algo *p)
+static inline ptrdiff_t hash_algo_by_ptr(const struct git_hash_algo *p)
{
return p - hash_algos;
}
diff --git a/strbuf.h b/strbuf.h
index c8d98dfb95..30659f2d5d 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -225,7 +225,7 @@ int strbuf_cmp(const struct strbuf *first, const struct
strbuf *second);
/**
* Add a single character to the buffer.
*/
-static inline void strbuf_addch(struct strbuf *sb, int c)
+static inline void strbuf_addch(struct strbuf *sb, char c)
{
if (!strbuf_avail(sb))
strbuf_grow(sb, 1);
--
2.21.0
