tools/examples/headrev.c

   1 /*
   2  * headrev.c :  print out the HEAD revision of a repository.
   3  *
   4  * ====================================================================
   5  * Copyright (c) 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  *  To compile on unix against Subversion and APR libraries, try
  19  *  something like:
  20  *
  21  *  cc headrev.c -o headrev \
  22  *  -I/usr/local/include/subversion-1 -I/usr/local/apache2/include \
  23  *  -L/usr/local/apache2/lib -L/usr/local/lib \
  24  *  -lsvn_client-1 -lsvn_ra-1 -lsvn_subr-1 -lapr-0 -laprutil-0
  25  *
  26  */
  27
  28 #include "svn_client.h"
  29 #include "svn_pools.h"
  30 #include "svn_config.h"
  31 #include "svn_fs.h"
  32 #include "svn_path.h"
  33 #include "svn_cmdline.h"
  34
  35
  36 /* Display a prompt and read a one-line response into the provided buffer,
  37    removing a trailing newline if present. */
  38 static svn_error_t *
  39 prompt_and_read_line(const char *prompt,
  40                      char *buffer,
  41                      size_t max)
  42 {
  43   int len;
  44   printf("%s: ", prompt);
  45   if (fgets(buffer, max, stdin) == NULL)
  46     return svn_error_create(0, NULL, "error reading stdin");
  47   len = strlen(buffer);
  48   if (len > 0 && buffer[len-1] == '\n')
  49     buffer[len-1] = 0;
  50   return SVN_NO_ERROR;
  51 }
  52
  53 /* A tiny callback function of type 'svn_auth_simple_prompt_func_t'. For
  54    a much better example, see svn_cl__auth_simple_prompt in the official
  55    svn cmdline client. */
  56 static svn_error_t *
  57 my_simple_prompt_callback (svn_auth_cred_simple_t **cred,
  58                            void *baton,
  59                            const char *realm,
  60                            const char *username,
  61                            svn_boolean_t may_save,
  62                            apr_pool_t *pool)
  63 {
  64   svn_auth_cred_simple_t *ret = apr_pcalloc (pool, sizeof (*ret));
  65   char answerbuf[100];
  66
  67   if (realm)
  68     {
  69       printf ("Authentication realm: %s\n", realm);
  70     }
  71
  72   if (username)
  73     ret->username = apr_pstrdup (pool, username);
  74   else
  75     {
  76       SVN_ERR (prompt_and_read_line("Username", answerbuf, sizeof(answerbuf)));
  77       ret->username = apr_pstrdup (pool, answerbuf);
  78     }
  79
  80   SVN_ERR (prompt_and_read_line("Password", answerbuf, sizeof(answerbuf)));
  81   ret->password = apr_pstrdup (pool, answerbuf);
  82
  83   *cred = ret;
  84   return SVN_NO_ERROR;
  85 }
  86
  87
  88 /* A tiny callback function of type 'svn_auth_username_prompt_func_t'. For
  89    a much better example, see svn_cl__auth_username_prompt in the official
  90    svn cmdline client. */
  91 static svn_error_t *
  92 my_username_prompt_callback (svn_auth_cred_username_t **cred,
  93                              void *baton,
  94                              const char *realm,
  95                              svn_boolean_t may_save,
  96                              apr_pool_t *pool)
  97 {
  98   svn_auth_cred_username_t *ret = apr_pcalloc (pool, sizeof (*ret));
  99   char answerbuf[100];
 100
 101   if (realm)
 102     {
 103       printf ("Authentication realm: %s\n", realm);
 104     }
 105
 106   SVN_ERR (prompt_and_read_line("Username", answerbuf, sizeof(answerbuf)));
 107   ret->username = apr_pstrdup (pool, answerbuf);
 108
 109   *cred = ret;
 110   return SVN_NO_ERROR;
 111 }
 112
 113
 114 /* A callback function used when the RA layer needs a handle to a
 115    temporary file.  This is a reduced version of the callback used in
 116    the official svn cmdline client. */
 117 static svn_error_t *
 118 open_tmp_file (apr_file_t **fp,
 119                void *callback_baton,
 120                apr_pool_t *pool)
 121 {
 122   const char *path;
 123   const char *ignored_filename;
 124
 125   SVN_ERR (svn_io_temp_dir (&path, pool));
 126   path = svn_path_join (path, "tempfile", pool);
 127
 128   /* Open a unique file, with delete-on-close set. */
 129   SVN_ERR (svn_io_open_unique_file2 (fp, &ignored_filename,
 130                                      path, ".tmp",
 131                                      svn_io_file_del_on_close, pool));
 132
 133   return SVN_NO_ERROR;
 134 }
 135
 136
 137 int
 138 main (int argc, const char **argv)
 139 {
 140   apr_pool_t *pool;
 141   svn_error_t *err;
 142   const char *URL;
 143   svn_ra_session_t  *session;
 144   svn_ra_callbacks2_t *cbtable;
 145   svn_revnum_t rev;
 146   apr_hash_t *cfg_hash;
 147   svn_auth_baton_t *auth_baton;
 148
 149   if (argc <= 1)
 150     {
 151       printf ("Usage:  %s URL\n", argv[0]);
 152       printf ("    Print HEAD revision of URL's repository.\n");
 153       return EXIT_FAILURE;
 154     }
 155   else
 156     URL = argv[1];
 157
 158   /* Initialize the app.  Send all error messages to 'stderr'.  */
 159   if (svn_cmdline_init ("headrev", stderr) != EXIT_SUCCESS)
 160     return EXIT_FAILURE;
 161
 162   /* Create top-level memory pool. Be sure to read the HACKING file to
 163      understand how to properly use/free subpools. */
 164   pool = svn_pool_create (NULL);
 165
 166   /* Initialize the FS library. */
 167   err = svn_fs_initialize (pool);
 168   if (err) goto hit_error;
 169
 170   /* Make sure the ~/.subversion run-time config files exist, and load. */
 171   err = svn_config_ensure (NULL, pool);
 172   if (err) goto hit_error;
 173
 174   err = svn_config_get_config (&cfg_hash, NULL, pool);
 175   if (err) goto hit_error;
 176
 177   /* Build an authentication baton. */
 178   {
 179     /* There are many different kinds of authentication back-end
 180        "providers".  See svn_auth.h for a full overview. */
 181     svn_auth_provider_object_t *provider;
 182     apr_array_header_t *providers
 183       = apr_array_make (pool, 4, sizeof (svn_auth_provider_object_t *));
 184
 185     svn_client_get_simple_prompt_provider (&provider,
 186                                            my_simple_prompt_callback,
 187                                            NULL, /* baton */
 188                                            2, /* retry limit */ pool);
 189     APR_ARRAY_PUSH (providers, svn_auth_provider_object_t *) = provider;
 190
 191     svn_client_get_username_prompt_provider (&provider,
 192                                              my_username_prompt_callback,
 193                                              NULL, /* baton */
 194                                              2, /* retry limit */ pool);
 195     APR_ARRAY_PUSH (providers, svn_auth_provider_object_t *) = provider;
 196
 197     /* Register the auth-providers into the context's auth_baton. */
 198     svn_auth_open (&auth_baton, providers, pool);
 199   }
 200
 201   /* Create a table of callbacks for the RA session, mostly nonexistent. */
 202   cbtable = apr_pcalloc (pool, sizeof(*cbtable));
 203   cbtable->auth_baton = auth_baton;
 204   cbtable->open_tmp_file = open_tmp_file;
 205
 206   /* Now do the real work. */
 207
 208   err = svn_ra_open2(&session, URL, cbtable, NULL, cfg_hash, pool);
 209   if (err) goto hit_error;
 210
 211   err = svn_ra_get_latest_revnum(session, &rev, pool);
 212   if (err) goto hit_error;
 213
 214   printf ("The latest revision is %ld.\n", rev);
 215
 216   return EXIT_SUCCESS;
 217
 218  hit_error:
 219   svn_handle_error2 (err, stderr, FALSE, "headrev: ");
 220   return EXIT_FAILURE;
 221 }