doc/fast-import: clarify how content states are built

diff --git a/wrapper.c b/wrapper.c
index 85f09df747637b94e0488ad65984c3f97c732034..68739aaa3b9e9e1a1bbbd43c75c9b5c244fb6c3e 100644 (file)
--- a/wrapper.c
+++ b/wrapper.c
@@ -9,6 +9,18 @@ static void do_nothing(size_t size)
 
 static void (*try_to_free_routine)(size_t size) = do_nothing;
 
+static void memory_limit_check(size_t size)
+{
+       static int limit = -1;
+       if (limit == -1) {
+               const char *env = getenv("GIT_ALLOC_LIMIT");
+               limit = env ? atoi(env) * 1024 : 0;
+       }
+       if (limit && size > limit)
+               die("attempting to allocate %"PRIuMAX" over limit %d",
+                   (intmax_t)size, limit);
+}
+
 try_to_free_t set_try_to_free_routine(try_to_free_t routine)
 {
        try_to_free_t old = try_to_free_routine;
@@ -32,7 +44,10 @@ char *xstrdup(const char *str)
 
 void *xmalloc(size_t size)
 {
-       void *ret = malloc(size);
+       void *ret;
+
+       memory_limit_check(size);
+       ret = malloc(size);
        if (!ret && !size)
                ret = malloc(1);
        if (!ret) {
@@ -79,7 +94,10 @@ char *xstrndup(const char *str, size_t len)
 
 void *xrealloc(void *ptr, size_t size)
 {
-       void *ret = realloc(ptr, size);
+       void *ret;
+
+       memory_limit_check(size);
+       ret = realloc(ptr, size);
        if (!ret && !size)
                ret = realloc(ptr, 1);
        if (!ret) {
@@ -95,7 +113,10 @@ void *xrealloc(void *ptr, size_t size)
 
 void *xcalloc(size_t nmemb, size_t size)
 {
-       void *ret = calloc(nmemb, size);
+       void *ret;
+
+       memory_limit_check(size * nmemb);
+       ret = calloc(nmemb, size);
        if (!ret && (!nmemb || !size))
                ret = calloc(1, 1);
        if (!ret) {
@@ -381,3 +402,28 @@ int remove_or_warn(unsigned int mode, const char *file)
 {
        return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file);
 }
+
+void warn_on_inaccessible(const char *path)
+{
+       warning(_("unable to access '%s': %s"), path, strerror(errno));
+}
+
+int access_or_warn(const char *path, int mode)
+{
+       int ret = access(path, mode);
+       if (ret && errno != ENOENT)
+               warn_on_inaccessible(path);
+       return ret;
+}
+
+struct passwd *xgetpwuid_self(void)
+{
+       struct passwd *pw;
+
+       errno = 0;
+       pw = getpwuid(getuid());
+       if (!pw)
+               die(_("unable to look up current user in the passwd file: %s"),
+                   errno ? strerror(errno) : _("no such user"));
+       return pw;
+}