src/transport.c

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7 #include "common.h"
   8 #include "git2/types.h"
   9 #include "git2/remote.h"
  10 #include "git2/net.h"
  11 #include "git2/transport.h"
  12 #include "path.h"
  13
  14 typedef struct transport_definition {
  15         char *prefix;
  16         unsigned priority;
  17         git_transport_cb fn;
  18         void *param;
  19 } transport_definition;
  20
  21 static transport_definition local_transport_definition = { "file://", 1, git_transport_local, NULL };
  22 static transport_definition dummy_transport_definition = { NULL, 1, git_transport_dummy, NULL };
  23
  24 static git_smart_subtransport_definition http_subtransport_definition = { git_smart_subtransport_http, 1 };
  25 static git_smart_subtransport_definition git_subtransport_definition = { git_smart_subtransport_git, 0 };
  26
  27 static transport_definition transports[] = {
  28         {"git://", 1, git_transport_smart, &git_subtransport_definition},
  29         {"http://", 1, git_transport_smart, &http_subtransport_definition},
  30         {"https://", 1, git_transport_smart, &http_subtransport_definition},
  31         {"file://", 1, git_transport_local, NULL},
  32         {"git+ssh://", 1, git_transport_dummy, NULL},
  33         {"ssh+git://", 1, git_transport_dummy, NULL},
  34         {NULL, 0, 0}
  35 };
  36
  37 #define GIT_TRANSPORT_COUNT (sizeof(transports)/sizeof(transports[0])) - 1
  38
  39 static int transport_find_fn(const char *url, git_transport_cb *callback, void **param)
  40 {
  41         size_t i = 0;
  42         unsigned priority = 0;
  43         transport_definition *definition = NULL, *definition_iter;
  44
  45         // First, check to see if it's an obvious URL, which a URL scheme
  46         for (i = 0; i < GIT_TRANSPORT_COUNT; ++i) {
  47                 definition_iter = &transports[i];
  48
  49                 if (strncasecmp(url, definition_iter->prefix, strlen(definition_iter->prefix)))
  50                         continue;
  51
  52                 if (definition_iter->priority > priority)
  53                         definition = definition_iter;
  54         }
  55
  56 #ifdef GIT_WIN32
  57         /* On Windows, it might not be possible to discern between absolute local
  58          * and ssh paths - first check if this is a valid local path that points
  59          * to a directory and if so assume local path, else assume SSH */
  60
  61         /* Check to see if the path points to a file on the local file system */
  62         if (!definition && git_path_exists(url) && git_path_isdir(url))
  63                 definition = &local_transport_definition;
  64
  65         /* It could be a SSH remote path. Check to see if there's a :
  66          * SSH is an unsupported transport mechanism in this version of libgit2 */
  67         if (!definition && strrchr(url, ':'))
  68                 definition = &dummy_transport_definition;
  69 #else
  70         /* For other systems, perform the SSH check first, to avoid going to the
  71          * filesystem if it is not necessary */
  72
  73         /* It could be a SSH remote path. Check to see if there's a :
  74          * SSH is an unsupported transport mechanism in this version of libgit2 */
  75         if (!definition && strrchr(url, ':'))
  76                 definition = &dummy_transport_definition;
  77
  78         /* Check to see if the path points to a file on the local file system */
  79         if (!definition && git_path_exists(url) && git_path_isdir(url))
  80                 definition = &local_transport_definition;
  81 #endif
  82
  83         if (!definition)
  84                 return -1;
  85
  86         *callback = definition->fn;
  87         *param = definition->param;
  88
  89         return 0;
  90 }
  91
  92 /**************
  93  * Public API *
  94  **************/
  95
  96 int git_transport_dummy(git_transport **transport, git_remote *owner, void *param)
  97 {
  98         GIT_UNUSED(transport);
  99         GIT_UNUSED(owner);
 100         GIT_UNUSED(param);
 101         giterr_set(GITERR_NET, "This transport isn't implemented. Sorry");
 102         return -1;
 103 }
 104
 105 int git_transport_new(git_transport **out, git_remote *owner, const char *url)
 106 {
 107         git_transport_cb fn;
 108         git_transport *transport;
 109         void *param;
 110         int error;
 111
 112         if (transport_find_fn(url, &fn, &param) < 0) {
 113                 giterr_set(GITERR_NET, "Unsupported URL protocol");
 114                 return -1;
 115         }
 116
 117         error = fn(&transport, owner, param);
 118         if (error < 0)
 119                 return error;
 120
 121         *out = transport;
 122
 123         return 0;
 124 }
 125
 126 /* from remote.h */
 127 int git_remote_valid_url(const char *url)
 128 {
 129         git_transport_cb fn;
 130         void *param;
 131
 132         return !transport_find_fn(url, &fn, &param);
 133 }
 134
 135 int git_remote_supported_url(const char* url)
 136 {
 137         git_transport_cb fn;
 138         void *param;
 139
 140         if (transport_find_fn(url, &fn, &param) < 0)
 141                 return 0;
 142
 143         return fn != &git_transport_dummy;
 144 }