prefer memcpy to strcpy

When we already know the length of a string (e.g., because
we just malloc'd to fit it), it's nicer to use memcpy than
strcpy, as it makes it more obvious that we are not going to
overflow the buffer (because the size we pass matches the
size in the allocation).

This also eliminates calls to strcpy, which make auditing
the code base harder.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/compat/nedmalloc/nedmalloc.c b/compat/nedmalloc/nedmalloc.c
index 609ebba..a0a16eb 100644 (file)
--- a/compat/nedmalloc/nedmalloc.c
+++ b/compat/nedmalloc/nedmalloc.c
@@ -957,8 +957,9 @@ char *strdup(const char *s1)
 {
        char *s2 = 0;
        if (s1) {
-               s2 = malloc(strlen(s1) + 1);
-               strcpy(s2, s1);
+               size_t len = strlen(s1) + 1;
+               s2 = malloc(len);
+               memcpy(s2, s1, len);
        }
        return s2;
 }

diff --git a/fast-import.c b/fast-import.c
index 895c6b4..cf6d8bc 100644 (file)
--- a/fast-import.c
+++ b/fast-import.c
@@ -644,8 +644,9 @@ static void *pool_calloc(size_t count, size_t size)
 
 static char *pool_strdup(const char *s)
 {
-       char *r = pool_alloc(strlen(s) + 1);
-       strcpy(r, s);
+       size_t len = strlen(s) + 1;
+       char *r = pool_alloc(len);
+       memcpy(r, s, len);
        return r;
 }
 

diff --git a/revision.c b/revision.c
index af2a18e..2236463 100644 (file)
--- a/revision.c
+++ b/revision.c
@@ -38,7 +38,7 @@ char *path_name(const struct name_path *path, const char *name)
        }
        n = xmalloc(len);
        m = n + len - (nlen + 1);
-       strcpy(m, name);
+       memcpy(m, name, nlen + 1);
        for (p = path; p; p = p->up) {
                if (p->elem_len) {
                        m -= p->elem_len + 1;