git-pickaxe: introduce heuristics to avoid "trivial" chunks

diff --git a/upload-pack.c b/upload-pack.c
index 27e2abe36c54fbf4ff04a70a64e1985fc4a8cbd0..189b239cc093ab1d585627a647c7c36bf65efe18 100644 (file)
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -4,6 +4,7 @@
 #include "cache.h"
 #include "refs.h"
 #include "pkt-line.h"
+#include "sideband.h"
 #include "tag.h"
 #include "object.h"
 #include "commit.h"
@@ -14,12 +15,15 @@ static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=n
 #define THEY_HAVE (1U << 0)
 #define OUR_REF (1U << 1)
 #define WANTED (1U << 2)
-static int multi_ack = 0, nr_our_refs = 0;
-static int use_thin_pack = 0;
+static int multi_ack, nr_our_refs;
+static int use_thin_pack;
 static struct object_array have_obj;
 static struct object_array want_obj;
-static unsigned int timeout = 0;
-static int use_sideband = 0;
+static unsigned int timeout;
+/* 0 for no sideband,
+ * otherwise maximum packet size (up to 65520 bytes).
+ */
+static int use_sideband;
 
 static void reset_timeout(void)
 {
@@ -33,45 +37,18 @@ static int strip(char *line, int len)
        return len;
 }
 
-#define PACKET_MAX 1000
 static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
 {
-       ssize_t ssz;
-       const char *p;
-
-       if (!data) {
-               if (!use_sideband)
-                       return 0;
-               packet_flush(1);
-       }
-
-       if (!use_sideband) {
-               if (fd == 3)
-                       /* emergency quit */
-                       fd = 2;
-               if (fd == 2) {
-                       xwrite(fd, data, sz);
-                       return sz;
-               }
-               return safe_write(fd, data, sz);
-       }
-       p = data;
-       ssz = sz;
-       while (sz) {
-               unsigned n;
-               char hdr[5];
-
-               n = sz;
-               if (PACKET_MAX - 5 < n)
-                       n = PACKET_MAX - 5;
-               sprintf(hdr, "%04x", n + 5);
-               hdr[4] = fd;
-               safe_write(1, hdr, 5);
-               safe_write(1, p, n);
-               p += n;
-               sz -= n;
+       if (use_sideband)
+               return send_sideband(1, fd, data, sz, use_sideband);
+       if (fd == 3)
+               /* emergency quit */
+               fd = 2;
+       if (fd == 2) {
+               xwrite(fd, data, sz);
+               return sz;
        }
-       return ssz;
+       return safe_write(fd, data, sz);
 }
 
 static void create_pack_file(void)
@@ -308,7 +285,8 @@ static void create_pack_file(void)
                                goto fail;
                        fprintf(stderr, "flushed.\n");
                }
-               send_client_data(1, NULL, 0);
+               if (use_sideband)
+                       packet_flush(1);
                return;
        }
  fail:
@@ -351,7 +329,8 @@ static int got_sha1(char *hex, unsigned char *sha1)
 static int get_common_commits(void)
 {
        static char line[1000];
-       unsigned char sha1[20], last_sha1[20];
+       unsigned char sha1[20];
+       char hex[41], last_hex[41];
        int len;
 
        track_object_refs = 0;
@@ -368,21 +347,22 @@ static int get_common_commits(void)
                }
                len = strip(line, len);
                if (!strncmp(line, "have ", 5)) {
-                       if (got_sha1(line+5, sha1) &&
-                           (multi_ack || have_obj.nr == 1)) {
-                               packet_write(1, "ACK %s%s\n",
-                                            sha1_to_hex(sha1),
-                                            multi_ack ?  " continue" : "");
-                               if (multi_ack)
-                                       memcpy(last_sha1, sha1, 20);
+                       if (got_sha1(line+5, sha1)) {
+                               memcpy(hex, sha1_to_hex(sha1), 41);
+                               if (multi_ack) {
+                                       const char *msg = "ACK %s continue\n";
+                                       packet_write(1, msg, hex);
+                                       memcpy(last_hex, hex, 41);
+                               }
+                               else if (have_obj.nr == 1)
+                                       packet_write(1, "ACK %s\n", hex);
                        }
                        continue;
                }
                if (!strcmp(line, "done")) {
                        if (have_obj.nr > 0) {
                                if (multi_ack)
-                                       packet_write(1, "ACK %s\n",
-                                                       sha1_to_hex(last_sha1));
+                                       packet_write(1, "ACK %s\n", last_hex);
                                return 0;
                        }
                        packet_write(1, "NAK\n");
@@ -413,8 +393,10 @@ static void receive_needs(void)
                        multi_ack = 1;
                if (strstr(line+45, "thin-pack"))
                        use_thin_pack = 1;
-               if (strstr(line+45, "side-band"))
-                       use_sideband = 1;
+               if (strstr(line+45, "side-band-64k"))
+                       use_sideband = LARGE_PACKET_MAX;
+               else if (strstr(line+45, "side-band"))
+                       use_sideband = DEFAULT_PACKET_MAX;
 
                /* We have sent all our refs already, and the other end
                 * should have chosen out of them; otherwise they are
@@ -436,7 +418,7 @@ static void receive_needs(void)
 
 static int send_ref(const char *refname, const unsigned char *sha1)
 {
-       static const char *capabilities = "multi_ack thin-pack side-band";
+       static const char *capabilities = "multi_ack thin-pack side-band side-band-64k";
        struct object *o = parse_object(sha1);
 
        if (!o)