Hi René
On 16/12/2023 10:47, René Scharfe wrote:
Use the data type bool and its values true and false to document the
binary return value of skip_prefix() and friends more explicitly.
This first use of stdbool.h, introduced with C99, is meant to check
whether there are platforms that claim support for C99, as tested by
7bc341e21b (git-compat-util: add a test balloon for C99 support,
2021-12-01), but still lack that header for some reason.
A fallback based on a wider type, e.g. int, would have to deal with
comparisons somehow to emulate that any non-zero value is true:
bool b1 = 1;
bool b2 = 2;
if (b1 == b2) puts("This is true.");
int i1 = 1;
int i2 = 2;
if (i1 == i2) puts("Not printed.");
#define BOOLEQ(a, b) (!(a) == !(b))
if (BOOLEQ(i1, i2)) puts("This is true.");
So we'd be better off using bool everywhere without a fallback, if
possible. That's why this patch doesn't include any.
Thanks for the comprehensive commit message, I agree that we'd be better
off avoiding adding a fallback. The patch looks good, I did wonder if we
really need to covert all of these functions for a test-balloon but the
patch is still pretty small overall.
Best Wishes
Phillip
Signed-off-by: René Scharfe <l.s.r@xxxxxx>
---
git-compat-util.h | 42 ++++++++++++++++++++++--------------------
1 file changed, 22 insertions(+), 20 deletions(-)
diff --git a/git-compat-util.h b/git-compat-util.h
index 3e7a59b5ff..603c97e3b3 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -225,6 +225,7 @@ struct strbuf;
#include <stddef.h>
#include <stdlib.h>
#include <stdarg.h>
+#include <stdbool.h>
#include <string.h>
#ifdef HAVE_STRINGS_H
#include <strings.h> /* for strcasecmp() */
@@ -684,11 +685,11 @@ report_fn get_warn_routine(void);
void set_die_is_recursing_routine(int (*routine)(void));
/*
- * If the string "str" begins with the string found in "prefix", return 1.
+ * If the string "str" begins with the string found in "prefix", return true.
* The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
* the string right after the prefix).
*
- * Otherwise, return 0 and leave "out" untouched.
+ * Otherwise, return false and leave "out" untouched.
*
* Examples:
*
@@ -699,57 +700,58 @@ void set_die_is_recursing_routine(int (*routine)(void));
* [skip prefix if present, otherwise use whole string]
* skip_prefix(name, "refs/heads/", &name);
*/
-static inline int skip_prefix(const char *str, const char *prefix,
- const char **out)
+static inline bool skip_prefix(const char *str, const char *prefix,
+ const char **out)
{
do {
if (!*prefix) {
*out = str;
- return 1;
+ return true;
}
} while (*str++ == *prefix++);
- return 0;
+ return false;
}
/*
* Like skip_prefix, but promises never to read past "len" bytes of the input
* buffer, and returns the remaining number of bytes in "out" via "outlen".
*/
-static inline int skip_prefix_mem(const char *buf, size_t len,
- const char *prefix,
- const char **out, size_t *outlen)
+static inline bool skip_prefix_mem(const char *buf, size_t len,
+ const char *prefix,
+ const char **out, size_t *outlen)
{
size_t prefix_len = strlen(prefix);
if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
*out = buf + prefix_len;
*outlen = len - prefix_len;
- return 1;
+ return true;
}
- return 0;
+ return false;
}
/*
- * If buf ends with suffix, return 1 and subtract the length of the suffix
- * from *len. Otherwise, return 0 and leave *len untouched.
+ * If buf ends with suffix, return true and subtract the length of the suffix
+ * from *len. Otherwise, return false and leave *len untouched.
*/
-static inline int strip_suffix_mem(const char *buf, size_t *len,
- const char *suffix)
+static inline bool strip_suffix_mem(const char *buf, size_t *len,
+ const char *suffix)
{
size_t suflen = strlen(suffix);
if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
- return 0;
+ return false;
*len -= suflen;
- return 1;
+ return true;
}
/*
- * If str ends with suffix, return 1 and set *len to the size of the string
- * without the suffix. Otherwise, return 0 and set *len to the size of the
+ * If str ends with suffix, return true and set *len to the size of the string
+ * without the suffix. Otherwise, return false and set *len to the size of the
* string.
*
* Note that we do _not_ NUL-terminate str to the new length.
*/
-static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
+static inline bool strip_suffix(const char *str, const char *suffix,
+ size_t *len)
{
*len = strlen(str);
return strip_suffix_mem(str, len, suffix);
--
2.43.0
