difftool --no-index: error out on --dir-diff (and don't crash)
[gitweb.git] / remote-curl.c
index aad02dcc74b61d0701f1dd599339430df90f8465..5b447949228cbf853f35ff9c3cccd4ea7a0f8afc 100644 (file)
@@ -505,8 +505,6 @@ static void output_refs(struct ref *refs)
 
 struct rpc_state {
        const char *service_name;
-       const char **argv;
-       struct strbuf *stdin_preamble;
        char *service_url;
        char *hdr_content_type;
        char *hdr_accept;
@@ -518,25 +516,121 @@ struct rpc_state {
        int in;
        int out;
        int any_written;
-       struct strbuf result;
        unsigned gzip_request : 1;
        unsigned initial_buffer : 1;
+
+       /*
+        * Whenever a pkt-line is read into buf, append the 4 characters
+        * denoting its length before appending the payload.
+        */
+       unsigned write_line_lengths : 1;
+
+       /*
+        * Used by rpc_out; initialize to 0. This is true if a flush has been
+        * read, but the corresponding line length (if write_line_lengths is
+        * true) and EOF have not been sent to libcurl. Since each flush marks
+        * the end of a request, each flush must be completely sent before any
+        * further reading occurs.
+        */
+       unsigned flush_read_but_not_sent : 1;
 };
 
+/*
+ * Appends the result of reading from rpc->out to the string represented by
+ * rpc->buf and rpc->len if there is enough space. Returns 1 if there was
+ * enough space, 0 otherwise.
+ *
+ * If rpc->write_line_lengths is true, appends the line length as a 4-byte
+ * hexadecimal string before appending the result described above.
+ *
+ * Writes the total number of bytes appended into appended.
+ */
+static int rpc_read_from_out(struct rpc_state *rpc, int options,
+                            size_t *appended,
+                            enum packet_read_status *status) {
+       size_t left;
+       char *buf;
+       int pktlen_raw;
+
+       if (rpc->write_line_lengths) {
+               left = rpc->alloc - rpc->len - 4;
+               buf = rpc->buf + rpc->len + 4;
+       } else {
+               left = rpc->alloc - rpc->len;
+               buf = rpc->buf + rpc->len;
+       }
+
+       if (left < LARGE_PACKET_MAX)
+               return 0;
+
+       *status = packet_read_with_status(rpc->out, NULL, NULL, buf,
+                       left, &pktlen_raw, options);
+       if (*status != PACKET_READ_EOF) {
+               *appended = pktlen_raw + (rpc->write_line_lengths ? 4 : 0);
+               rpc->len += *appended;
+       }
+
+       if (rpc->write_line_lengths) {
+               switch (*status) {
+               case PACKET_READ_EOF:
+                       if (!(options & PACKET_READ_GENTLE_ON_EOF))
+                               die("shouldn't have EOF when not gentle on EOF");
+                       break;
+               case PACKET_READ_NORMAL:
+                       set_packet_header(buf - 4, *appended);
+                       break;
+               case PACKET_READ_DELIM:
+                       memcpy(buf - 4, "0001", 4);
+                       break;
+               case PACKET_READ_FLUSH:
+                       memcpy(buf - 4, "0000", 4);
+                       break;
+               }
+       }
+
+       return 1;
+}
+
 static size_t rpc_out(void *ptr, size_t eltsize,
                size_t nmemb, void *buffer_)
 {
        size_t max = eltsize * nmemb;
        struct rpc_state *rpc = buffer_;
        size_t avail = rpc->len - rpc->pos;
+       enum packet_read_status status;
 
        if (!avail) {
                rpc->initial_buffer = 0;
-               avail = packet_read(rpc->out, NULL, NULL, rpc->buf, rpc->alloc, 0);
-               if (!avail)
-                       return 0;
+               rpc->len = 0;
                rpc->pos = 0;
-               rpc->len = avail;
+               if (!rpc->flush_read_but_not_sent) {
+                       if (!rpc_read_from_out(rpc, 0, &avail, &status))
+                               BUG("The entire rpc->buf should be larger than LARGE_PACKET_MAX");
+                       if (status == PACKET_READ_FLUSH)
+                               rpc->flush_read_but_not_sent = 1;
+               }
+               /*
+                * If flush_read_but_not_sent is true, we have already read one
+                * full request but have not fully sent it + EOF, which is why
+                * we need to refrain from reading.
+                */
+       }
+       if (rpc->flush_read_but_not_sent) {
+               if (!avail) {
+                       /*
+                        * The line length either does not need to be sent at
+                        * all or has already been completely sent. Now we can
+                        * return 0, indicating EOF, meaning that the flush has
+                        * been fully sent.
+                        */
+                       rpc->flush_read_but_not_sent = 0;
+                       return 0;
+               }
+               /*
+                * If avail is non-zerp, the line length for the flush still
+                * hasn't been fully sent. Proceed with sending the line
+                * length.
+                */
        }
 
        if (max < avail)
@@ -664,7 +758,11 @@ static curl_off_t xcurl_off_t(size_t len)
        return (curl_off_t)size;
 }
 
-static int post_rpc(struct rpc_state *rpc)
+/*
+ * If flush_received is true, do not attempt to read any more; just use what's
+ * in rpc->buf.
+ */
+static int post_rpc(struct rpc_state *rpc, int flush_received)
 {
        struct active_request_slot *slot;
        struct curl_slist *headers = http_copy_default_headers();
@@ -679,21 +777,19 @@ static int post_rpc(struct rpc_state *rpc)
         * allocated buffer space we can use HTTP/1.0 and avoid the
         * chunked encoding mess.
         */
-       while (1) {
-               size_t left = rpc->alloc - rpc->len;
-               char *buf = rpc->buf + rpc->len;
-               int n;
-
-               if (left < LARGE_PACKET_MAX) {
-                       large_request = 1;
-                       use_gzip = 0;
-                       break;
+       if (!flush_received) {
+               while (1) {
+                       size_t n;
+                       enum packet_read_status status;
+
+                       if (!rpc_read_from_out(rpc, 0, &n, &status)) {
+                               large_request = 1;
+                               use_gzip = 0;
+                               break;
+                       }
+                       if (status == PACKET_READ_FLUSH)
+                               break;
                }
-
-               n = packet_read(rpc->out, NULL, NULL, buf, left, 0);
-               if (!n)
-                       break;
-               rpc->len += n;
        }
 
        if (large_request) {
@@ -829,22 +925,22 @@ static int post_rpc(struct rpc_state *rpc)
        return err;
 }
 
-static int rpc_service(struct rpc_state *rpc, struct discovery *heads)
+static int rpc_service(struct rpc_state *rpc, struct discovery *heads,
+                      const char **client_argv, const struct strbuf *preamble,
+                      struct strbuf *rpc_result)
 {
        const char *svc = rpc->service_name;
        struct strbuf buf = STRBUF_INIT;
-       struct strbuf *preamble = rpc->stdin_preamble;
        struct child_process client = CHILD_PROCESS_INIT;
        int err = 0;
 
        client.in = -1;
        client.out = -1;
        client.git_cmd = 1;
-       client.argv = rpc->argv;
+       client.argv = client_argv;
        if (start_command(&client))
                exit(1);
-       if (preamble)
-               write_or_die(client.in, preamble->buf, preamble->len);
+       write_or_die(client.in, preamble->buf, preamble->len);
        if (heads)
                write_or_die(client.in, heads->buf, heads->len);
 
@@ -852,7 +948,6 @@ static int rpc_service(struct rpc_state *rpc, struct discovery *heads)
        rpc->buf = xmalloc(rpc->alloc);
        rpc->in = client.in;
        rpc->out = client.out;
-       strbuf_init(&rpc->result, 0);
 
        strbuf_addf(&buf, "%s%s", url.buf, svc);
        rpc->service_url = strbuf_detach(&buf, NULL);
@@ -874,13 +969,13 @@ static int rpc_service(struct rpc_state *rpc, struct discovery *heads)
                        break;
                rpc->pos = 0;
                rpc->len = n;
-               err |= post_rpc(rpc);
+               err |= post_rpc(rpc, 0);
        }
 
        close(client.in);
        client.in = -1;
        if (!err) {
-               strbuf_read(&rpc->result, client.out, 0);
+               strbuf_read(rpc_result, client.out, 0);
        } else {
                char buf[4096];
                for (;;)
@@ -933,6 +1028,7 @@ static int fetch_git(struct discovery *heads,
        struct strbuf preamble = STRBUF_INIT;
        int i, err;
        struct argv_array args = ARGV_ARRAY_INIT;
+       struct strbuf rpc_result = STRBUF_INIT;
 
        argv_array_pushl(&args, "fetch-pack", "--stateless-rpc",
                         "--stdin", "--lock-pack", NULL);
@@ -978,14 +1074,12 @@ static int fetch_git(struct discovery *heads,
 
        memset(&rpc, 0, sizeof(rpc));
        rpc.service_name = "git-upload-pack",
-       rpc.argv = args.argv;
-       rpc.stdin_preamble = &preamble;
        rpc.gzip_request = 1;
 
-       err = rpc_service(&rpc, heads);
-       if (rpc.result.len)
-               write_or_die(1, rpc.result.buf, rpc.result.len);
-       strbuf_release(&rpc.result);
+       err = rpc_service(&rpc, heads, args.argv, &preamble, &rpc_result);
+       if (rpc_result.len)
+               write_or_die(1, rpc_result.buf, rpc_result.len);
+       strbuf_release(&rpc_result);
        strbuf_release(&preamble);
        argv_array_clear(&args);
        return err;
@@ -1080,6 +1174,7 @@ static int push_git(struct discovery *heads, int nr_spec, char **specs)
        struct argv_array args;
        struct string_list_item *cas_option;
        struct strbuf preamble = STRBUF_INIT;
+       struct strbuf rpc_result = STRBUF_INIT;
 
        argv_array_init(&args);
        argv_array_pushl(&args, "send-pack", "--stateless-rpc", "--helper-status",
@@ -1112,13 +1207,11 @@ static int push_git(struct discovery *heads, int nr_spec, char **specs)
 
        memset(&rpc, 0, sizeof(rpc));
        rpc.service_name = "git-receive-pack",
-       rpc.argv = args.argv;
-       rpc.stdin_preamble = &preamble;
 
-       err = rpc_service(&rpc, heads);
-       if (rpc.result.len)
-               write_or_die(1, rpc.result.buf, rpc.result.len);
-       strbuf_release(&rpc.result);
+       err = rpc_service(&rpc, heads, args.argv, &preamble, &rpc_result);
+       if (rpc_result.len)
+               write_or_die(1, rpc_result.buf, rpc_result.len);
+       strbuf_release(&rpc_result);
        strbuf_release(&preamble);
        argv_array_clear(&args);
        return err;
@@ -1170,165 +1263,11 @@ static void parse_push(struct strbuf *buf)
        free(specs);
 }
 
-/*
- * Used to represent the state of a connection to an HTTP server when
- * communicating using git's wire-protocol version 2.
- */
-struct proxy_state {
-       char *service_name;
-       char *service_url;
-       struct curl_slist *headers;
-       struct strbuf request_buffer;
-       int in;
-       int out;
-       struct packet_reader reader;
-       size_t pos;
-       int seen_flush;
-};
-
-static void proxy_state_init(struct proxy_state *p, const char *service_name,
-                            enum protocol_version version)
-{
-       struct strbuf buf = STRBUF_INIT;
-
-       memset(p, 0, sizeof(*p));
-       p->service_name = xstrdup(service_name);
-
-       p->in = 0;
-       p->out = 1;
-       strbuf_init(&p->request_buffer, 0);
-
-       strbuf_addf(&buf, "%s%s", url.buf, p->service_name);
-       p->service_url = strbuf_detach(&buf, NULL);
-
-       p->headers = http_copy_default_headers();
-
-       strbuf_addf(&buf, "Content-Type: application/x-%s-request", p->service_name);
-       p->headers = curl_slist_append(p->headers, buf.buf);
-       strbuf_reset(&buf);
-
-       strbuf_addf(&buf, "Accept: application/x-%s-result", p->service_name);
-       p->headers = curl_slist_append(p->headers, buf.buf);
-       strbuf_reset(&buf);
-
-       p->headers = curl_slist_append(p->headers, "Transfer-Encoding: chunked");
-
-       /* Add the Git-Protocol header */
-       if (get_protocol_http_header(version, &buf))
-               p->headers = curl_slist_append(p->headers, buf.buf);
-
-       packet_reader_init(&p->reader, p->in, NULL, 0,
-                          PACKET_READ_GENTLE_ON_EOF |
-                          PACKET_READ_DIE_ON_ERR_PACKET);
-
-       strbuf_release(&buf);
-}
-
-static void proxy_state_clear(struct proxy_state *p)
-{
-       free(p->service_name);
-       free(p->service_url);
-       curl_slist_free_all(p->headers);
-       strbuf_release(&p->request_buffer);
-}
-
-/*
- * CURLOPT_READFUNCTION callback function.
- * Attempts to copy over a single packet-line at a time into the
- * curl provided buffer.
- */
-static size_t proxy_in(char *buffer, size_t eltsize,
-                      size_t nmemb, void *userdata)
-{
-       size_t max;
-       struct proxy_state *p = userdata;
-       size_t avail = p->request_buffer.len - p->pos;
-
-
-       if (eltsize != 1)
-               BUG("curl read callback called with size = %"PRIuMAX" != 1",
-                   (uintmax_t)eltsize);
-       max = nmemb;
-
-       if (!avail) {
-               if (p->seen_flush) {
-                       p->seen_flush = 0;
-                       return 0;
-               }
-
-               strbuf_reset(&p->request_buffer);
-               switch (packet_reader_read(&p->reader)) {
-               case PACKET_READ_EOF:
-                       die("unexpected EOF when reading from parent process");
-               case PACKET_READ_NORMAL:
-                       packet_buf_write_len(&p->request_buffer, p->reader.line,
-                                            p->reader.pktlen);
-                       break;
-               case PACKET_READ_DELIM:
-                       packet_buf_delim(&p->request_buffer);
-                       break;
-               case PACKET_READ_FLUSH:
-                       packet_buf_flush(&p->request_buffer);
-                       p->seen_flush = 1;
-                       break;
-               }
-               p->pos = 0;
-               avail = p->request_buffer.len;
-       }
-
-       if (max < avail)
-               avail = max;
-       memcpy(buffer, p->request_buffer.buf + p->pos, avail);
-       p->pos += avail;
-       return avail;
-}
-
-static size_t proxy_out(char *buffer, size_t eltsize,
-                       size_t nmemb, void *userdata)
-{
-       size_t size;
-       struct proxy_state *p = userdata;
-
-       if (eltsize != 1)
-               BUG("curl read callback called with size = %"PRIuMAX" != 1",
-                   (uintmax_t)eltsize);
-       size = nmemb;
-
-       write_or_die(p->out, buffer, size);
-       return size;
-}
-
-/* Issues a request to the HTTP server configured in `p` */
-static int proxy_request(struct proxy_state *p)
-{
-       struct active_request_slot *slot;
-
-       slot = get_active_slot();
-
-       curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
-       curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
-       curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
-       curl_easy_setopt(slot->curl, CURLOPT_URL, p->service_url);
-       curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, p->headers);
-
-       /* Setup function to read request from client */
-       curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, proxy_in);
-       curl_easy_setopt(slot->curl, CURLOPT_READDATA, p);
-
-       /* Setup function to write server response to client */
-       curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, proxy_out);
-       curl_easy_setopt(slot->curl, CURLOPT_WRITEDATA, p);
-
-       if (run_slot(slot, NULL) != HTTP_OK)
-               return -1;
-
-       return 0;
-}
-
 static int stateless_connect(const char *service_name)
 {
        struct discovery *discover;
-       struct proxy_state p;
+       struct rpc_state rpc;
+       struct strbuf buf = STRBUF_INIT;
 
        /*
         * Run the info/refs request and see if the server supports protocol
@@ -1348,23 +1287,58 @@ static int stateless_connect(const char *service_name)
                fflush(stdout);
        }
 
-       proxy_state_init(&p, service_name, discover->version);
+       rpc.service_name = service_name;
+       rpc.service_url = xstrfmt("%s%s", url.buf, rpc.service_name);
+       rpc.hdr_content_type = xstrfmt("Content-Type: application/x-%s-request", rpc.service_name);
+       rpc.hdr_accept = xstrfmt("Accept: application/x-%s-result", rpc.service_name);
+       if (get_protocol_http_header(discover->version, &buf)) {
+               rpc.protocol_header = strbuf_detach(&buf, NULL);
+       } else {
+               rpc.protocol_header = NULL;
+               strbuf_release(&buf);
+       }
+       rpc.buf = xmalloc(http_post_buffer);
+       rpc.alloc = http_post_buffer;
+       rpc.len = 0;
+       rpc.pos = 0;
+       rpc.in = 1;
+       rpc.out = 0;
+       rpc.any_written = 0;
+       rpc.gzip_request = 1;
+       rpc.initial_buffer = 0;
+       rpc.write_line_lengths = 1;
+       rpc.flush_read_but_not_sent = 0;
 
        /*
         * Dump the capability listing that we got from the server earlier
         * during the info/refs request.
         */
-       write_or_die(p.out, discover->buf, discover->len);
+       write_or_die(rpc.in, discover->buf, discover->len);
+
+       /* Until we see EOF keep sending POSTs */
+       while (1) {
+               size_t avail;
+               enum packet_read_status status;
 
-       /* Peek the next packet line.  Until we see EOF keep sending POSTs */
-       while (packet_reader_peek(&p.reader) != PACKET_READ_EOF) {
-               if (proxy_request(&p)) {
+               if (!rpc_read_from_out(&rpc, PACKET_READ_GENTLE_ON_EOF, &avail,
+                                      &status))
+                       BUG("The entire rpc->buf should be larger than LARGE_PACKET_MAX");
+               if (status == PACKET_READ_EOF)
+                       break;
+               if (post_rpc(&rpc, status == PACKET_READ_FLUSH))
                        /* We would have an err here */
                        break;
-               }
+               /* Reset the buffer for next request */
+               rpc.len = 0;
        }
 
-       proxy_state_clear(&p);
+       free(rpc.service_url);
+       free(rpc.hdr_content_type);
+       free(rpc.hdr_accept);
+       free(rpc.protocol_header);
+       free(rpc.buf);
+       strbuf_release(&buf);
+
        return 0;
 }