src/bin/psql/prompt.c

   1 /*
   2  * psql - the PostgreSQL interactive terminal
   3  *
   4  * Copyright (c) 2000-2008, PostgreSQL Global Development Group
   5  *
   6  * $PostgreSQL$
   7  */
   8 #include "postgres_fe.h"
   9
  10 #ifdef WIN32
  11 #include <io.h>
  12 #include <win32.h>
  13 #endif
  14
  15 #ifdef HAVE_UNIX_SOCKETS
  16 #include <unistd.h>
  17 #include <netdb.h>
  18 #endif
  19
  20 #include "common.h"
  21 #include "input.h"
  22 #include "prompt.h"
  23 #include "settings.h"
  24
  25
  26 /*--------------------------
  27  * get_prompt
  28  *
  29  * Returns a statically allocated prompt made by interpolating certain
  30  * tcsh style escape sequences into pset.vars "PROMPT1|2|3".
  31  * (might not be completely multibyte safe)
  32  *
  33  * Defined interpolations are:
  34  * %M - database server "hostname.domainname", "[local]" for AF_UNIX
  35  *              sockets, "[local:/dir/name]" if not default
  36  * %m - like %M, but hostname only (before first dot), or always "[local]"
  37  * %> - database server port number
  38  * %n - database user name
  39  * %/ - current database
  40  * %~ - like %/ but "~" when database name equals user name
  41  * %# - "#" if superuser, ">" otherwise
  42  * %R - in prompt1 normally =, or ^ if single line mode,
  43  *                      or a ! if session is not connected to a database;
  44  *              in prompt2 -, *, ', or ";
  45  *              in prompt3 nothing
  46  * %x - transaction status: empty, *, !, ? (unknown or no connection)
  47  * %? - the error code of the last query (not yet implemented)
  48  * %% - a percent sign
  49  *
  50  * %[0-9]                  - the character with the given decimal code
  51  * %0[0-7]                 - the character with the given octal code
  52  * %0x[0-9A-Fa-f]  - the character with the given hexadecimal code
  53  *
  54  * %`command`      - The result of executing command in /bin/sh with trailing
  55  *                                       newline stripped.
  56  * %:name:                 - The value of the psql variable 'name'
  57  * (those will not be rescanned for more escape sequences!)
  58  *
  59  * %[ ... %]       - tell readline that the contained text is invisible
  60  *
  61  * If the application-wide prompts become NULL somehow, the returned string
  62  * will be empty (not NULL!).
  63  *--------------------------
  64  */
  65
  66 char *
  67 get_prompt(promptStatus_t status)
  68 {
  69 #define MAX_PROMPT_SIZE 256
  70         static char destination[MAX_PROMPT_SIZE + 1];
  71         char            buf[MAX_PROMPT_SIZE + 1];
  72         bool            esc = false;
  73         const char *p;
  74         const char *prompt_string = "? ";
  75
  76         switch (status)
  77         {
  78                 case PROMPT_READY:
  79                         prompt_string = pset.prompt1;
  80                         break;
  81
  82                 case PROMPT_CONTINUE:
  83                 case PROMPT_SINGLEQUOTE:
  84                 case PROMPT_DOUBLEQUOTE:
  85                 case PROMPT_DOLLARQUOTE:
  86                 case PROMPT_COMMENT:
  87                 case PROMPT_PAREN:
  88                         prompt_string = pset.prompt2;
  89                         break;
  90
  91                 case PROMPT_COPY:
  92                         prompt_string = pset.prompt3;
  93                         break;
  94         }
  95
  96         destination[0] = '\0';
  97
  98         for (p = prompt_string;
  99                  *p && strlen(destination) < sizeof(destination) - 1;
 100                  p++)
 101         {
 102                 memset(buf, 0, sizeof(buf));
 103                 if (esc)
 104                 {
 105                         switch (*p)
 106                         {
 107                                         /* Current database */
 108                                 case '/':
 109                                         if (pset.db)
 110                                                 strlcpy(buf, PQdb(pset.db), sizeof(buf));
 111                                         break;
 112                                 case '~':
 113                                         if (pset.db)
 114                                         {
 115                                                 const char *var;
 116
 117                                                 if (strcmp(PQdb(pset.db), PQuser(pset.db)) == 0 ||
 118                                                         ((var = getenv("PGDATABASE")) && strcmp(var, PQdb(pset.db)) == 0))
 119                                                         strlcpy(buf, "~", sizeof(buf));
 120                                                 else
 121                                                         strlcpy(buf, PQdb(pset.db), sizeof(buf));
 122                                         }
 123                                         break;
 124
 125                                         /* DB server hostname (long/short) */
 126                                 case 'M':
 127                                 case 'm':
 128                                         if (pset.db)
 129                                         {
 130                                                 const char *host = PQhost(pset.db);
 131
 132                                                 /* INET socket */
 133                                                 if (host && host[0] && !is_absolute_path(host))
 134                                                 {
 135                                                         strlcpy(buf, host, sizeof(buf));
 136                                                         if (*p == 'm')
 137                                                                 buf[strcspn(buf, ".")] = '\0';
 138                                                 }
 139 #ifdef HAVE_UNIX_SOCKETS
 140                                                 /* UNIX socket */
 141                                                 else
 142                                                 {
 143                                                         if (!host
 144                                                                 || strcmp(host, DEFAULT_PGSOCKET_DIR) == 0
 145                                                                 || *p == 'm')
 146                                                                 strlcpy(buf, "[local]", sizeof(buf));
 147                                                         else
 148                                                                 snprintf(buf, sizeof(buf), "[local:%s]", host);
 149                                                 }
 150 #endif
 151                                         }
 152                                         break;
 153                                         /* DB server port number */
 154                                 case '>':
 155                                         if (pset.db && PQport(pset.db))
 156                                                 strlcpy(buf, PQport(pset.db), sizeof(buf));
 157                                         break;
 158                                         /* DB server user name */
 159                                 case 'n':
 160                                         if (pset.db)
 161                                                 strlcpy(buf, session_username(), sizeof(buf));
 162                                         break;
 163
 164                                 case '0':
 165                                 case '1':
 166                                 case '2':
 167                                 case '3':
 168                                 case '4':
 169                                 case '5':
 170                                 case '6':
 171                                 case '7':
 172                                         *buf = (char) strtol(p, (char **) &p, 8);
 173                                         --p;
 174                                         break;
 175                                 case 'R':
 176                                         switch (status)
 177                                         {
 178                                                 case PROMPT_READY:
 179                                                         if (!pset.db)
 180                                                                 buf[0] = '!';
 181                                                         else if (!pset.singleline)
 182                                                                 buf[0] = '=';
 183                                                         else
 184                                                                 buf[0] = '^';
 185                                                         break;
 186                                                 case PROMPT_CONTINUE:
 187                                                         buf[0] = '-';
 188                                                         break;
 189                                                 case PROMPT_SINGLEQUOTE:
 190                                                         buf[0] = '\'';
 191                                                         break;
 192                                                 case PROMPT_DOUBLEQUOTE:
 193                                                         buf[0] = '"';
 194                                                         break;
 195                                                 case PROMPT_DOLLARQUOTE:
 196                                                         buf[0] = '$';
 197                                                         break;
 198                                                 case PROMPT_COMMENT:
 199                                                         buf[0] = '*';
 200                                                         break;
 201                                                 case PROMPT_PAREN:
 202                                                         buf[0] = '(';
 203                                                         break;
 204                                                 default:
 205                                                         buf[0] = '\0';
 206                                                         break;
 207                                         }
 208                                         break;
 209
 210                                 case 'x':
 211                                         if (!pset.db)
 212                                                 buf[0] = '?';
 213                                         else
 214                                                 switch (PQtransactionStatus(pset.db))
 215                                                 {
 216                                                         case PQTRANS_IDLE:
 217                                                                 buf[0] = '\0';
 218                                                                 break;
 219                                                         case PQTRANS_ACTIVE:
 220                                                         case PQTRANS_INTRANS:
 221                                                                 buf[0] = '*';
 222                                                                 break;
 223                                                         case PQTRANS_INERROR:
 224                                                                 buf[0] = '!';
 225                                                                 break;
 226                                                         default:
 227                                                                 buf[0] = '?';
 228                                                                 break;
 229                                                 }
 230                                         break;
 231
 232                                 case '?':
 233                                         /* not here yet */
 234                                         break;
 235
 236                                 case '#':
 237                                         if (is_superuser())
 238                                                 buf[0] = '#';
 239                                         else
 240                                                 buf[0] = '>';
 241                                         break;
 242
 243                                         /* execute command */
 244                                 case '`':
 245                                         {
 246                                                 FILE       *fd;
 247                                                 char       *file = pg_strdup(p + 1);
 248                                                 int                     cmdend;
 249
 250                                                 cmdend = strcspn(file, "`");
 251                                                 file[cmdend] = '\0';
 252                                                 fd = popen(file, "r");
 253                                                 if (fd)
 254                                                 {
 255                                                         fgets(buf, sizeof(buf), fd);
 256                                                         pclose(fd);
 257                                                 }
 258                                                 if (strlen(buf) > 0 && buf[strlen(buf) - 1] == '\n')
 259                                                         buf[strlen(buf) - 1] = '\0';
 260                                                 free(file);
 261                                                 p += cmdend + 1;
 262                                                 break;
 263                                         }
 264
 265                                         /* interpolate variable */
 266                                 case ':':
 267                                         {
 268                                                 char       *name;
 269                                                 const char *val;
 270                                                 int                     nameend;
 271
 272                                                 name = pg_strdup(p + 1);
 273                                                 nameend = strcspn(name, ":");
 274                                                 name[nameend] = '\0';
 275                                                 val = GetVariable(pset.vars, name);
 276                                                 if (val)
 277                                                         strlcpy(buf, val, sizeof(buf));
 278                                                 free(name);
 279                                                 p += nameend + 1;
 280                                                 break;
 281                                         }
 282
 283                                 case '[':
 284                                 case ']':
 285 #if defined(USE_READLINE) && defined(RL_PROMPT_START_IGNORE)
 286
 287                                         /*
 288                                          * readline >=4.0 undocumented feature: non-printing
 289                                          * characters in prompt strings must be marked as such, in
 290                                          * order to properly display the line during editing.
 291                                          */
 292                                         buf[0] = (*p == '[') ? RL_PROMPT_START_IGNORE : RL_PROMPT_END_IGNORE;
 293                                         buf[1] = '\0';
 294 #endif   /* USE_READLINE */
 295                                         break;
 296
 297                                 default:
 298                                         buf[0] = *p;
 299                                         buf[1] = '\0';
 300                                         break;
 301
 302                         }
 303                         esc = false;
 304                 }
 305                 else if (*p == '%')
 306                         esc = true;
 307                 else
 308                 {
 309                         buf[0] = *p;
 310                         buf[1] = '\0';
 311                         esc = false;
 312                 }
 313
 314                 if (!esc)
 315                         strlcat(destination, buf, sizeof(destination));
 316         }
 317
 318         return destination;
 319 }