git-http-fetch: Remove size limit for objects/info/{packs,alternates}

git-http-fetch received objects/info/packs into a fixed-size buffer
and started to fail when this file became larger than the buffer.
Change it to grow the buffer dynamically, and do the same thing for
objects/info/alternates.  Also add missing free() calls for these
buffers.

Signed-off-by: Sergey Vlasov <vsu@altlinux.ru>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/http-fetch.c b/http-fetch.c
index 0aba891..c6daf6a 100644 (file)
--- a/http-fetch.c
+++ b/http-fetch.c
@@ -110,6 +110,22 @@ static size_t fwrite_buffer(void *ptr, size_t eltsize, size_t nmemb,
         return size;
 }
 
+static size_t fwrite_buffer_dynamic(const void *ptr, size_t eltsize,
+                                   size_t nmemb, struct buffer *buffer)
+{
+       size_t size = eltsize * nmemb;
+       if (size > buffer->size - buffer->posn) {
+               buffer->size = buffer->size * 3 / 2;
+               if (buffer->size < buffer->posn + size)
+                       buffer->size = buffer->posn + size;
+               buffer->buffer = xrealloc(buffer->buffer, buffer->size);
+       }
+       memcpy(buffer->buffer + buffer->posn, ptr, size);
+       buffer->posn += size;
+       data_received++;
+       return size;
+}
+
 static size_t fwrite_sha1_file(void *ptr, size_t eltsize, size_t nmemb,
                               void *data)
 {
@@ -618,11 +634,12 @@ static int fetch_alternates(char *base)
        int i = 0;
        int http_specific = 1;
        struct alt_base *tail = alt;
+       static const char null_byte = '\0';
 
        struct active_request_slot *slot;
 
        data = xmalloc(4096);
-       buffer.size = 4095;
+       buffer.size = 4096;
        buffer.posn = 0;
        buffer.buffer = data;
 
@@ -634,7 +651,8 @@ static int fetch_alternates(char *base)
 
        slot = get_active_slot();
        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
-       curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
+       curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
+                        fwrite_buffer_dynamic);
        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
        if (start_active_slot(slot)) {
                run_active_slot(slot);
@@ -646,20 +664,24 @@ static int fetch_alternates(char *base)
                        slot = get_active_slot();
                        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
                        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
-                                        fwrite_buffer);
+                                        fwrite_buffer_dynamic);
                        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
                        if (start_active_slot(slot)) {
                                run_active_slot(slot);
                                if (slot->curl_result != CURLE_OK) {
+                                       free(buffer.buffer);
                                        return 0;
                                }
                        }
                }
        } else {
+               free(buffer.buffer);
                return 0;
        }
 
-       data[buffer.posn] = '\0';
+       fwrite_buffer_dynamic(&null_byte, 1, 1, &buffer);
+       buffer.posn--;
+       data = buffer.buffer;
 
        while (i < buffer.posn) {
                int posn = i;
@@ -718,7 +740,8 @@ static int fetch_alternates(char *base)
                }
                i = posn + 1;
        }
-       
+
+       free(buffer.buffer);
        return ret;
 }
 
@@ -748,17 +771,22 @@ static int fetch_indices(struct alt_base *repo)
 
        slot = get_active_slot();
        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
-       curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
+       curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
+                        fwrite_buffer_dynamic);
        curl_easy_setopt(slot->curl, CURLOPT_URL, url);
        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
        if (start_active_slot(slot)) {
                run_active_slot(slot);
-               if (slot->curl_result != CURLE_OK)
+               if (slot->curl_result != CURLE_OK) {
+                       free(buffer.buffer);
                        return error("%s", curl_errorstr);
+               }
        } else {
+               free(buffer.buffer);
                return error("Unable to start request");
        }
 
+       data = buffer.buffer;
        while (i < buffer.posn) {
                switch (data[i]) {
                case 'P':
@@ -778,6 +806,7 @@ static int fetch_indices(struct alt_base *repo)
                i++;
        }
 
+       free(buffer.buffer);
        repo->got_indices = 1;
        return 0;
 }