[PATCH 01/11] argv-array: use size_t for count and alloc

From: Jeff King <peff@peff.net>
Date: Jul 28, 2020, 20:21 UTC
Message-ID: <20200728202152.GA1021513@coredump.intra.peff.net>
In-Reply-To: <20200728202124.GA1021264@coredump.intra.peff.net>

On most 64-bit platforms, "int" is significantly smaller than a size_t, which could lead to integer overflow and under-allocation of the array. It's probably impossible to trigger in practice, as it would imply on the order of 2^32 individual allocations. Even if was possible to grow an array in that way (and we typically only use it for sets of strings, like command line options), each allocation needs a pointer, malloc overhead, etc. You'd quite likely run out of RAM before succeeding in such an overflow.

But all that hand-waving aside, it's easy enough to use the correct type, so let's do so.

Signed-off-by: Jeff King <peff@peff.net>
---
This one is obviously of value even without the renaming.

 argv-array.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/argv-array.h b/argv-array.h
index a7d3b10707..4fc57b6902 100644
--- a/argv-array.h
+++ b/argv-array.h
@@ -29,8 +29,8 @@ extern const char *empty_argv[];
  */
 struct argv_array {
 	const char **argv;
-	int argc;
-	int alloc;
+	size_t argc;
+	size_t alloc;
 };
 
 #define ARGV_ARRAY_INIT { empty_argv, 0, 0 }

-- 
2.28.0.rc2.475.g53c7e1c7f4