Refactor merge strategies into separate includable file.
[gitweb.git] / connect.c
index 941bf296b0d5a8ded60cea0ed61770dc909d2d88..c2badc71aa2ccf63fa6d9ef02a5ee76feb54e5c9 100644 (file)
--- a/connect.c
+++ b/connect.c
@@ -1,5 +1,87 @@
 #include "cache.h"
+#include "pkt-line.h"
+#include "quote.h"
+#include "refs.h"
 #include <sys/wait.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+
+static char *server_capabilities = NULL;
+
+/*
+ * Read all the refs from the other end
+ */
+struct ref **get_remote_heads(int in, struct ref **list,
+                             int nr_match, char **match, int ignore_funny)
+{
+       *list = NULL;
+       for (;;) {
+               struct ref *ref;
+               unsigned char old_sha1[20];
+               static char buffer[1000];
+               char *name;
+               int len, name_len;
+
+               len = packet_read_line(in, buffer, sizeof(buffer));
+               if (!len)
+                       break;
+               if (buffer[len-1] == '\n')
+                       buffer[--len] = 0;
+
+               if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
+                       die("protocol error: expected sha/ref, got '%s'", buffer);
+               name = buffer + 41;
+
+               if (ignore_funny && 45 < len && !memcmp(name, "refs/", 5) &&
+                   check_ref_format(name + 5))
+                       continue;
+
+               name_len = strlen(name);
+               if (len != name_len + 41) {
+                       if (server_capabilities)
+                               free(server_capabilities);
+                       server_capabilities = strdup(name + name_len + 1);
+               }
+
+               if (nr_match && !path_match(name, nr_match, match))
+                       continue;
+               ref = xcalloc(1, sizeof(*ref) + len - 40);
+               memcpy(ref->old_sha1, old_sha1, 20);
+               memcpy(ref->name, buffer + 41, len - 40);
+               *list = ref;
+               list = &ref->next;
+       }
+       return list;
+}
+
+int server_supports(const char *feature)
+{
+       return server_capabilities &&
+               strstr(server_capabilities, feature) != NULL;
+}
+
+int get_ack(int fd, unsigned char *result_sha1)
+{
+       static char line[1000];
+       int len = packet_read_line(fd, line, sizeof(line));
+
+       if (!len)
+               die("git-fetch-pack: expected ACK/NAK, got EOF");
+       if (line[len-1] == '\n')
+               line[--len] = 0;
+       if (!strcmp(line, "NAK"))
+               return 0;
+       if (!strncmp(line, "ACK ", 3)) {
+               if (!get_sha1_hex(line+4, result_sha1)) {
+                       if (strstr(line+45, "continue"))
+                               return 2;
+                       return 1;
+               }
+       }
+       die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
+}
 
 int path_match(const char *path, int nr, char **match)
 {
@@ -22,65 +104,410 @@ int path_match(const char *path, int nr, char **match)
        return 0;
 }
 
+struct refspec {
+       char *src;
+       char *dst;
+       char force;
+};
+
 /*
- * First, make it shell-safe.  We do this by just disallowing any
- * special characters. Somebody who cares can do escaping and let
- * through the rest. But since we're doing to feed this to ssh as
- * a command line, we're going to be pretty damn anal for now.
+ * A:B means fast forward remote B with local A.
+ * +A:B means overwrite remote B with local A.
+ * +A is a shorthand for +A:A.
+ * A is a shorthand for A:A.
  */
-static char *shell_safe(char *url)
-{
-       char *n = url;
-       unsigned char c;
-       static const char flags[256] = {
-               ['0'...'9'] = 1,
-               ['a'...'z'] = 1,
-               ['A'...'Z'] = 1,
-               ['.'] = 1, ['/'] = 1,
-               ['-'] = 1, ['+'] = 1,
-               [':'] = 1
-       };
-
-       while ((c = *n++) != 0) {
-               if (flags[c] != 1)
-                       die("I don't like '%c'. Sue me.", c);
+static struct refspec *parse_ref_spec(int nr_refspec, char **refspec)
+{
+       int i;
+       struct refspec *rs = xcalloc(sizeof(*rs), (nr_refspec + 1));
+       for (i = 0; i < nr_refspec; i++) {
+               char *sp, *dp, *ep;
+               sp = refspec[i];
+               if (*sp == '+') {
+                       rs[i].force = 1;
+                       sp++;
+               }
+               ep = strchr(sp, ':');
+               if (ep) {
+                       dp = ep + 1;
+                       *ep = 0;
+               }
+               else
+                       dp = sp;
+               rs[i].src = sp;
+               rs[i].dst = dp;
        }
-       return url;
+       rs[nr_refspec].src = rs[nr_refspec].dst = NULL;
+       return rs;
 }
 
+static int count_refspec_match(const char *pattern,
+                              struct ref *refs,
+                              struct ref **matched_ref)
+{
+       int match;
+       int patlen = strlen(pattern);
+
+       for (match = 0; refs; refs = refs->next) {
+               char *name = refs->name;
+               int namelen = strlen(name);
+               if (namelen < patlen ||
+                   memcmp(name + namelen - patlen, pattern, patlen))
+                       continue;
+               if (namelen != patlen && name[namelen - patlen - 1] != '/')
+                       continue;
+               match++;
+               *matched_ref = refs;
+       }
+       return match;
+}
+
+static void link_dst_tail(struct ref *ref, struct ref ***tail)
+{
+       **tail = ref;
+       *tail = &ref->next;
+       **tail = NULL;
+}
+
+static struct ref *try_explicit_object_name(const char *name)
+{
+       unsigned char sha1[20];
+       struct ref *ref;
+       int len;
+       if (get_sha1(name, sha1))
+               return NULL;
+       len = strlen(name) + 1;
+       ref = xcalloc(1, sizeof(*ref) + len);
+       memcpy(ref->name, name, len);
+       memcpy(ref->new_sha1, sha1, 20);
+       return ref;
+}
+
+static int match_explicit_refs(struct ref *src, struct ref *dst,
+                              struct ref ***dst_tail, struct refspec *rs)
+{
+       int i, errs;
+       for (i = errs = 0; rs[i].src; i++) {
+               struct ref *matched_src, *matched_dst;
+
+               matched_src = matched_dst = NULL;
+               switch (count_refspec_match(rs[i].src, src, &matched_src)) {
+               case 1:
+                       break;
+               case 0:
+                       /* The source could be in the get_sha1() format
+                        * not a reference name.
+                        */
+                       matched_src = try_explicit_object_name(rs[i].src);
+                       if (matched_src)
+                               break;
+                       errs = 1;
+                       error("src refspec %s does not match any.",
+                             rs[i].src);
+                       break;
+               default:
+                       errs = 1;
+                       error("src refspec %s matches more than one.",
+                             rs[i].src);
+                       break;
+               }
+               switch (count_refspec_match(rs[i].dst, dst, &matched_dst)) {
+               case 1:
+                       break;
+               case 0:
+                       if (!memcmp(rs[i].dst, "refs/", 5)) {
+                               int len = strlen(rs[i].dst) + 1;
+                               matched_dst = xcalloc(1, sizeof(*dst) + len);
+                               memcpy(matched_dst->name, rs[i].dst, len);
+                               link_dst_tail(matched_dst, dst_tail);
+                       }
+                       else if (!strcmp(rs[i].src, rs[i].dst) &&
+                                matched_src) {
+                               /* pushing "master:master" when
+                                * remote does not have master yet.
+                                */
+                               int len = strlen(matched_src->name) + 1;
+                               matched_dst = xcalloc(1, sizeof(*dst) + len);
+                               memcpy(matched_dst->name, matched_src->name,
+                                      len);
+                               link_dst_tail(matched_dst, dst_tail);
+                       }
+                       else {
+                               errs = 1;
+                               error("dst refspec %s does not match any "
+                                     "existing ref on the remote and does "
+                                     "not start with refs/.", rs[i].dst);
+                       }
+                       break;
+               default:
+                       errs = 1;
+                       error("dst refspec %s matches more than one.",
+                             rs[i].dst);
+                       break;
+               }
+               if (errs)
+                       continue;
+               if (matched_dst->peer_ref) {
+                       errs = 1;
+                       error("dst ref %s receives from more than one src.",
+                             matched_dst->name);
+               }
+               else {
+                       matched_dst->peer_ref = matched_src;
+                       matched_dst->force = rs[i].force;
+               }
+       }
+       return -errs;
+}
+
+static struct ref *find_ref_by_name(struct ref *list, const char *name)
+{
+       for ( ; list; list = list->next)
+               if (!strcmp(list->name, name))
+                       return list;
+       return NULL;
+}
+
+int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
+              int nr_refspec, char **refspec, int all)
+{
+       struct refspec *rs = parse_ref_spec(nr_refspec, refspec);
+
+       if (nr_refspec)
+               return match_explicit_refs(src, dst, dst_tail, rs);
+
+       /* pick the remainder */
+       for ( ; src; src = src->next) {
+               struct ref *dst_peer;
+               if (src->peer_ref)
+                       continue;
+               dst_peer = find_ref_by_name(dst, src->name);
+               if ((dst_peer && dst_peer->peer_ref) || (!dst_peer && !all))
+                       continue;
+               if (!dst_peer) {
+                       /* Create a new one and link it */
+                       int len = strlen(src->name) + 1;
+                       dst_peer = xcalloc(1, sizeof(*dst_peer) + len);
+                       memcpy(dst_peer->name, src->name, len);
+                       memcpy(dst_peer->new_sha1, src->new_sha1, 20);
+                       link_dst_tail(dst_peer, dst_tail);
+               }
+               dst_peer->peer_ref = src;
+       }
+       return 0;
+}
+
+enum protocol {
+       PROTO_LOCAL = 1,
+       PROTO_SSH,
+       PROTO_GIT,
+};
+
+static enum protocol get_protocol(const char *name)
+{
+       if (!strcmp(name, "ssh"))
+               return PROTO_SSH;
+       if (!strcmp(name, "git"))
+               return PROTO_GIT;
+       if (!strcmp(name, "git+ssh"))
+               return PROTO_SSH;
+       if (!strcmp(name, "ssh+git"))
+               return PROTO_SSH;
+       die("I don't handle protocol '%s'", name);
+}
+
+#define STR_(s)        # s
+#define STR(s) STR_(s)
+
+#ifndef NO_IPV6
+
+static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
+{
+       int sockfd = -1;
+       char *colon, *end;
+       char *port = STR(DEFAULT_GIT_PORT);
+       struct addrinfo hints, *ai0, *ai;
+       int gai;
+
+       if (host[0] == '[') {
+               end = strchr(host + 1, ']');
+               if (end) {
+                       *end = 0;
+                       end++;
+                       host++;
+               } else
+                       end = host;
+       } else
+               end = host;
+       colon = strchr(end, ':');
+
+       if (colon) {
+               *colon = 0;
+               port = colon + 1;
+       }
+
+       memset(&hints, 0, sizeof(hints));
+       hints.ai_socktype = SOCK_STREAM;
+       hints.ai_protocol = IPPROTO_TCP;
+
+       gai = getaddrinfo(host, port, &hints, &ai);
+       if (gai)
+               die("Unable to look up %s (%s)", host, gai_strerror(gai));
+
+       for (ai0 = ai; ai; ai = ai->ai_next) {
+               sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
+               if (sockfd < 0)
+                       continue;
+               if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
+                       close(sockfd);
+                       sockfd = -1;
+                       continue;
+               }
+               break;
+       }
+
+       freeaddrinfo(ai0);
+
+       if (sockfd < 0)
+               die("unable to connect a socket (%s)", strerror(errno));
+
+       fd[0] = sockfd;
+       fd[1] = sockfd;
+       packet_write(sockfd, "%s %s\n", prog, path);
+       return 0;
+}
+
+#else /* NO_IPV6 */
+
+static int git_tcp_connect(int fd[2], const char *prog, char *host, char *path)
+{
+       int sockfd = -1;
+       char *colon, *end;
+       char *port = STR(DEFAULT_GIT_PORT), *ep;
+       struct hostent *he;
+       struct sockaddr_in sa;
+       char **ap;
+       unsigned int nport;
+
+       if (host[0] == '[') {
+               end = strchr(host + 1, ']');
+               if (end) {
+                       *end = 0;
+                       end++;
+                       host++;
+               } else
+                       end = host;
+       } else
+               end = host;
+       colon = strchr(end, ':');
+
+       if (colon) {
+               *colon = 0;
+               port = colon + 1;
+       }
+
+
+       he = gethostbyname(host);
+       if (!he)
+               die("Unable to look up %s (%s)", host, hstrerror(h_errno));
+       nport = strtoul(port, &ep, 10);
+       if ( ep == port || *ep ) {
+               /* Not numeric */
+               struct servent *se = getservbyname(port,"tcp");
+               if ( !se )
+                       die("Unknown port %s\n", port);
+               nport = se->s_port;
+       }
+
+       for (ap = he->h_addr_list; *ap; ap++) {
+               sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
+               if (sockfd < 0)
+                       continue;
+
+               memset(&sa, 0, sizeof sa);
+               sa.sin_family = he->h_addrtype;
+               sa.sin_port = htons(nport);
+               memcpy(&sa.sin_addr, ap, he->h_length);
+
+               if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
+                       close(sockfd);
+                       sockfd = -1;
+                       continue;
+               }
+               break;
+       }
+
+       if (sockfd < 0)
+               die("unable to connect a socket (%s)", strerror(errno));
+
+       fd[0] = sockfd;
+       fd[1] = sockfd;
+       packet_write(sockfd, "%s %s\n", prog, path);
+       return 0;
+}
+
+#endif /* NO_IPV6 */
+
 /*
  * Yeah, yeah, fixme. Need to pass in the heads etc.
  */
 int git_connect(int fd[2], char *url, const char *prog)
 {
        char command[1024];
-       const char *host, *path;
+       char *host, *path;
        char *colon;
        int pipefd[2][2];
        pid_t pid;
+       enum protocol protocol;
 
-       url = shell_safe(url);
        host = NULL;
        path = url;
        colon = strchr(url, ':');
+       protocol = PROTO_LOCAL;
        if (colon) {
                *colon = 0;
                host = url;
                path = colon+1;
+               protocol = PROTO_SSH;
+               if (!memcmp(path, "//", 2)) {
+                       char *slash = strchr(path + 2, '/');
+                       if (slash) {
+                               int nr = slash - path - 2;
+                               memmove(path, path+2, nr);
+                               path[nr] = 0;
+                               protocol = get_protocol(url);
+                               host = path;
+                               path = slash;
+                       }
+               }
        }
-       snprintf(command, sizeof(command), "%s %s", prog, path);
+
+       if (protocol == PROTO_GIT)
+               return git_tcp_connect(fd, prog, host, path);
+
        if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
                die("unable to create pipe pair for communication");
        pid = fork();
        if (!pid) {
+               snprintf(command, sizeof(command), "%s %s", prog,
+                        sq_quote(path));
                dup2(pipefd[1][0], 0);
                dup2(pipefd[0][1], 1);
                close(pipefd[0][0]);
                close(pipefd[0][1]);
                close(pipefd[1][0]);
                close(pipefd[1][1]);
-               if (host)
-                       execlp("ssh", "ssh", host, command, NULL);
+               if (protocol == PROTO_SSH) {
+                       const char *ssh, *ssh_basename;
+                       ssh = getenv("GIT_SSH");
+                       if (!ssh) ssh = "ssh";
+                       ssh_basename = strrchr(ssh, '/');
+                       if (!ssh_basename)
+                               ssh_basename = ssh;
+                       else
+                               ssh_basename++;
+                       execlp(ssh, ssh_basename, host, command, NULL);
+               }
                else
                        execlp("sh", "sh", "-c", command, NULL);
                die("exec failed");