tools/examples/minimal_client.c

   1 /*
   2  * minimal_client.c  - a minimal Subversion client application ("hello world")
   3  *
   4  * ====================================================================
   5  * Copyright (c) 2000-2004 CollabNet.  All rights reserved.
   6  *
   7  * This software is licensed as described in the file COPYING, which
   8  * you should have received as part of this distribution.  The terms
   9  * are also available at http://subversion.tigris.org/license-1.html.
  10  * If newer versions of this license are posted there, you may use a
  11  * newer version instead, at your option.
  12  *
  13  * This software consists of voluntary contributions made by many
  14  * individuals.  For exact contribution history, see the revision
  15  * history and logs, available at http://subversion.tigris.org/.
  16  * ====================================================================
  17  *
  18  *  This app demonstrates how to use the svn_client.h API.
  19  *
  20  *  It reads a directory URL from the commandline, runs
  21  *  svn_client_list() and prints the list of directory-entries.  It
  22  *  also knows how to deal with basic username/password authentication
  23  *  challenges.
  24  *
  25  *  For a much more complex example, the svn cmdline client might be
  26  *  considered the 'reference implementation'.
  27  *
  28  *  From a Linux system, a typical commandline compile might look like:
  29  *
  30  *  cc minimal_client.c -o minimal_client \
  31  *  -I/usr/local/include/subversion-1 -I/usr/local/apache2/include \
  32  *  -L/usr/local/apache2/lib -L/usr/local/lib \
  33  *  -lsvn_client-1 -lapr-0 -laprutil-0
  34  *
  35  */
  36
  37
  38 #include "svn_client.h"
  39 #include "svn_cmdline.h"
  40 #include "svn_pools.h"
  41 #include "svn_config.h"
  42 #include "svn_fs.h"
  43
  44
  45 /* Display a prompt and read a one-line response into the provided buffer,
  46    removing a trailing newline if present. */
  47 static svn_error_t *
  48 prompt_and_read_line(const char *prompt,
  49                      char *buffer,
  50                      size_t max)
  51 {
  52   int len;
  53   printf("%s: ", prompt);
  54   if (fgets(buffer, max, stdin) == NULL)
  55     return svn_error_create(0, NULL, "error reading stdin");
  56   len = strlen(buffer);
  57   if (len > 0 && buffer[len-1] == '\n')
  58     buffer[len-1] = 0;
  59   return SVN_NO_ERROR;
  60 }
  61
  62 /* A tiny callback function of type 'svn_auth_simple_prompt_func_t'. For
  63    a much better example, see svn_cl__auth_simple_prompt in the official
  64    svn cmdline client. */
  65 static svn_error_t *
  66 my_simple_prompt_callback (svn_auth_cred_simple_t **cred,
  67                            void *baton,
  68                            const char *realm,
  69                            const char *username,
  70                            svn_boolean_t may_save,
  71                            apr_pool_t *pool)
  72 {
  73   svn_auth_cred_simple_t *ret = apr_pcalloc (pool, sizeof (*ret));
  74   char answerbuf[100];
  75
  76   if (realm)
  77     {
  78       printf ("Authentication realm: %s\n", realm);
  79     }
  80
  81   if (username)
  82     ret->username = apr_pstrdup (pool, username);
  83   else
  84     {
  85       SVN_ERR (prompt_and_read_line("Username", answerbuf, sizeof(answerbuf)));
  86       ret->username = apr_pstrdup (pool, answerbuf);
  87     }
  88
  89   SVN_ERR (prompt_and_read_line("Password", answerbuf, sizeof(answerbuf)));
  90   ret->password = apr_pstrdup (pool, answerbuf);
  91
  92   *cred = ret;
  93   return SVN_NO_ERROR;
  94 }
  95
  96
  97 /* A tiny callback function of type 'svn_auth_username_prompt_func_t'. For
  98    a much better example, see svn_cl__auth_username_prompt in the official
  99    svn cmdline client. */
 100 static svn_error_t *
 101 my_username_prompt_callback (svn_auth_cred_username_t **cred,
 102                              void *baton,
 103                              const char *realm,
 104                              svn_boolean_t may_save,
 105                              apr_pool_t *pool)
 106 {
 107   svn_auth_cred_username_t *ret = apr_pcalloc (pool, sizeof (*ret));
 108   char answerbuf[100];
 109
 110   if (realm)
 111     {
 112       printf ("Authentication realm: %s\n", realm);
 113     }
 114
 115   SVN_ERR (prompt_and_read_line("Username", answerbuf, sizeof(answerbuf)));
 116   ret->username = apr_pstrdup (pool, answerbuf);
 117
 118   *cred = ret;
 119   return SVN_NO_ERROR;
 120 }
 121
 122
 123
 124 int
 125 main (int argc, const char **argv)
 126 {
 127   apr_pool_t *pool;
 128   svn_error_t *err;
 129   svn_opt_revision_t revision;
 130   apr_hash_t *dirents;
 131   apr_hash_index_t *hi;
 132   svn_client_ctx_t *ctx;
 133   const char *URL;
 134
 135   if (argc <= 1)
 136     {
 137       printf ("Usage:  %s URL\n", argv[0]);
 138       return EXIT_FAILURE;
 139     }
 140   else
 141     URL = argv[1];
 142
 143   /* Initialize the app.  Send all error messages to 'stderr'.  */
 144   if (svn_cmdline_init ("minimal_client", stderr) != EXIT_SUCCESS)
 145     return EXIT_FAILURE;
 146
 147   /* Create top-level memory pool. Be sure to read the HACKING file to
 148      understand how to properly use/free subpools. */
 149   pool = svn_pool_create (NULL);
 150
 151   /* Initialize the FS library. */
 152   err = svn_fs_initialize (pool);
 153   if (err)
 154     {
 155       /* For functions deeper in the stack, we usually use the
 156          SVN_ERR() exception-throwing macro (see svn_error.h).  At the
 157          top level, we catch & print the error with svn_handle_error2(). */
 158       svn_handle_error2 (err, stderr, FALSE, "minimal_client: ");
 159       return EXIT_FAILURE;
 160     }
 161
 162   /* Make sure the ~/.subversion run-time config files exist */
 163   err = svn_config_ensure (NULL, pool);
 164   if (err)
 165     {
 166       svn_handle_error2 (err, stderr, FALSE, "minimal_client: ");
 167       return EXIT_FAILURE;
 168     }
 169
 170   /* All clients need to fill out a client_ctx object. */
 171   {
 172     /* Initialize and allocate the client_ctx object. */
 173     if ((err = svn_client_create_context (&ctx, pool)))
 174       {
 175         svn_handle_error2 (err, stderr, FALSE, "minimal_client: ");
 176         return EXIT_FAILURE;
 177       }
 178
 179     /* Load the run-time config file into a hash */
 180     if ((err = svn_config_get_config (&(ctx->config), NULL, pool)))
 181       {
 182         svn_handle_error2 (err, stderr, FALSE, "minimal_client: ");
 183         return EXIT_FAILURE;
 184       }
 185
 186 #ifdef WIN32
 187     /* Set the working copy administrative directory name. */
 188     if (getenv ("SVN_ASP_DOT_NET_HACK"))
 189       {
 190         err = svn_wc_set_adm_dir ("_svn", pool);
 191         if (err)
 192           {
 193             svn_handle_error2 (err, stderr, FALSE, "minimal_client: ");
 194             return EXIT_FAILURE;
 195           }
 196       }
 197 #endif
 198
 199     /* Depending on what your client does, you'll want to read about
 200        (and implement) the various callback function types below.  */
 201
 202     /* A func (& context) which receives event signals during
 203        checkouts, updates, commits, etc.  */
 204     /* ctx->notify_func = my_notification_func;
 205        ctx->notify_baton = NULL; */
 206
 207     /* A func (& context) which can receive log messages */
 208     /* ctx->log_msg_func = my_log_msg_receiver_func;
 209        ctx->log_msg_baton = NULL; */
 210
 211     /* A func (& context) which checks whether the user cancelled */
 212     /* ctx->cancel_func = my_cancel_checking_func;
 213        ctx->cancel_baton = NULL; */
 214
 215     /* Make the client_ctx capable of authenticating users */
 216     {
 217       /* There are many different kinds of authentication back-end
 218          "providers".  See svn_auth.h for a full overview.
 219
 220          If you want to get the auth behavior of the 'svn' program,
 221          you can use svn_cmdline_setup_auth_baton, which will give
 222          you the exact set of auth providers it uses.  This program
 223          doesn't use it because it's only appropriate for a command
 224          line program, and this is supposed to be a general purpose
 225          example. */
 226
 227       svn_auth_provider_object_t *provider;
 228       apr_array_header_t *providers
 229         = apr_array_make (pool, 4, sizeof (svn_auth_provider_object_t *));
 230
 231       svn_auth_get_simple_prompt_provider (&provider,
 232                                            my_simple_prompt_callback,
 233                                            NULL, /* baton */
 234                                            2, /* retry limit */ pool);
 235       APR_ARRAY_PUSH (providers, svn_auth_provider_object_t *) = provider;
 236
 237       svn_auth_get_username_prompt_provider (&provider,
 238                                              my_username_prompt_callback,
 239                                              NULL, /* baton */
 240                                              2, /* retry limit */ pool);
 241       APR_ARRAY_PUSH (providers, svn_auth_provider_object_t *) = provider;
 242
 243       /* Register the auth-providers into the context's auth_baton. */
 244       svn_auth_open (&ctx->auth_baton, providers, pool);
 245     }
 246   } /* end of client_ctx setup */
 247
 248
 249   /* Now do the real work. */
 250
 251   /* Set revision to always be the HEAD revision.  It could, however,
 252      be set to a specific revision number, date, or other values. */
 253   revision.kind = svn_opt_revision_head;
 254
 255   /* Main call into libsvn_client does all the work. */
 256   err = svn_client_ls (&dirents,
 257                        URL, &revision,
 258                        FALSE, /* no recursion */
 259                        ctx, pool);
 260   if (err)
 261     {
 262       svn_handle_error2 (err, stderr, FALSE, "minimal_client: ");
 263       return EXIT_FAILURE;
 264     }
 265
 266   /* Print the dir entries in the hash. */
 267   for (hi = apr_hash_first (pool, dirents); hi; hi = apr_hash_next (hi))
 268     {
 269       const char *entryname;
 270       svn_dirent_t *val;
 271
 272       apr_hash_this (hi, (void *) &entryname, NULL, (void *) &val);
 273       printf ("   %s\n", entryname);
 274
 275       /* 'val' is actually an svn_dirent_t structure; a more complex
 276           program would mine it for extra printable information. */
 277     }
 278
 279   return EXIT_SUCCESS;
 280 }