git-compat-util.h: introduce u32_add()

ttaylorr · gitster · commit 35364d7abaf9 · 2025-12-07T07:38:08.000+09:00
A future commit will want to add two 32-bit unsigned values together
while checking for overflow. Introduce a variant of the u64_add()
function for operating on 32-bit inputs.

Signed-off-by: Taylor Blau &lt;me@ttaylorr.com&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/git-compat-util.h b/git-compat-util.h
@@ -670,6 +670,14 @@ static inline int cast_size_t_to_int(size_t a)
 	return (int)a;
 }
 
+static inline uint32_t u32_add(uint32_t a, uint32_t b)
+{
+	if (unsigned_add_overflows(a, b))
+		die("uint32_t overflow: %"PRIuMAX" + %"PRIuMAX,
+		    (uintmax_t)a, (uintmax_t)b);
+	return a + b;
+}
+
 static inline uint64_t u64_mult(uint64_t a, uint64_t b)
 {
 	if (unsigned_mult_overflows(a, b))

Original file line number	Diff line number	Diff line change
`@@ -670,6 +670,14 @@ static inline int cast_size_t_to_int(size_t a)`
`670`	`670`	`return (int)a;`
`671`	`671`	`}`
`672`	`672`
	`673`	`+static inline uint32_t u32_add(uint32_t a, uint32_t b)`
	`674`	`+{`
	`675`	`+ if (unsigned_add_overflows(a, b))`
	`676`	`+ die("uint32_t overflow: %"PRIuMAX" + %"PRIuMAX,`
	`677`	`+ (uintmax_t)a, (uintmax_t)b);`
	`678`	`+ return a + b;`
	`679`	`+}`
	`680`	`+`
`673`	`681`	`static inline uint64_t u64_mult(uint64_t a, uint64_t b)`
`674`	`682`	`{`
`675`	`683`	`if (unsigned_mult_overflows(a, b))`