[v9,1/8] git-compat-util: add strtoul_ul() with error handling

Commit Message

Eric Ju Jan. 8, 2025, 6:37 p.m. UTC

We already have strtoul_ui() and similar functions that provide proper
error handling using strtoul from the standard library. However,
there isn't currently a variant that returns an unsigned long.
This commit introduces strtoul_ul() to address this gap, enabling the
return of an unsigned long with proper error handling.
---
 git-compat-util.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

Patch

diff --git a/git-compat-util.h b/git-compat-util.h
index e283c46c6f..3bdb085624 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1351,6 +1351,24 @@  static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 	return 0;
 }
 
+// Converts a string to an unsigned long using the standard library's strtoul,
+// with additional error handling to ensure robustness.
+static inline int strtoul_ul(char const *s, int base, unsigned long *result)
+{
+	unsigned long ul;
+	char *p;
+
+	errno = 0;
+	/* negative values would be accepted by strtoul */
+	if (strchr(s, '-'))
+		return -1;
+	ul = strtoul(s, &p, base);
+	if (errno || *p || p == s )
+		return -1;
+	*result = ul;
+	return 0;
+}
+
 static inline int strtol_i(char const *s, int base, int *result)
 {
 	long ul;