src/port/sprompt.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * sprompt.c
   4  *        simple_prompt() routine
   5  *
   6  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        $PostgreSQL$
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15
  16
  17 /*
  18  * simple_prompt
  19  *
  20  * Generalized function especially intended for reading in usernames and
  21  * password interactively. Reads from /dev/tty or stdin/stderr.
  22  *
  23  * prompt:              The prompt to print
  24  * maxlen:              How many characters to accept
  25  * echo:                Set to false if you want to hide what is entered (for passwords)
  26  *
  27  * Returns a malloc()'ed string with the input (w/o trailing newline).
  28  */
  29 #include "c.h"
  30
  31 #ifdef HAVE_TERMIOS_H
  32 #include <termios.h>
  33 #endif
  34
  35 extern char *simple_prompt(const char *prompt, int maxlen, bool echo);
  36
  37 char *
  38 simple_prompt(const char *prompt, int maxlen, bool echo)
  39 {
  40         int                     length;
  41         char       *destination;
  42         FILE       *termin,
  43                            *termout;
  44
  45 #ifdef HAVE_TERMIOS_H
  46         struct termios t_orig,
  47                                 t;
  48 #else
  49 #ifdef WIN32
  50         HANDLE          t = NULL;
  51         LPDWORD         t_orig = NULL;
  52 #endif
  53 #endif
  54
  55         destination = (char *) malloc(maxlen + 1);
  56         if (!destination)
  57                 return NULL;
  58
  59         /*
  60          * Do not try to collapse these into one "w+" mode file. Doesn't work on
  61          * some platforms (eg, HPUX 10.20).
  62          */
  63         termin = fopen(DEVTTY, "r");
  64         termout = fopen(DEVTTY, "w");
  65         if (!termin || !termout
  66 #ifdef WIN32
  67         /* See DEVTTY comment for msys */
  68                 || (getenv("OSTYPE") && strcmp(getenv("OSTYPE"), "msys") == 0)
  69 #endif
  70                 )
  71         {
  72                 if (termin)
  73                         fclose(termin);
  74                 if (termout)
  75                         fclose(termout);
  76                 termin = stdin;
  77                 termout = stderr;
  78         }
  79
  80 #ifdef HAVE_TERMIOS_H
  81         if (!echo)
  82         {
  83                 tcgetattr(fileno(termin), &t);
  84                 t_orig = t;
  85                 t.c_lflag &= ~ECHO;
  86                 tcsetattr(fileno(termin), TCSAFLUSH, &t);
  87         }
  88 #else
  89 #ifdef WIN32
  90         if (!echo)
  91         {
  92                 /* get a new handle to turn echo off */
  93                 t_orig = (LPDWORD) malloc(sizeof(DWORD));
  94                 t = GetStdHandle(STD_INPUT_HANDLE);
  95
  96                 /* save the old configuration first */
  97                 GetConsoleMode(t, t_orig);
  98
  99                 /* set to the new mode */
 100                 SetConsoleMode(t, ENABLE_LINE_INPUT | ENABLE_PROCESSED_INPUT);
 101         }
 102 #endif
 103 #endif
 104
 105         if (prompt)
 106         {
 107                 fputs(_(prompt), termout);
 108                 fflush(termout);
 109         }
 110
 111         if (fgets(destination, maxlen + 1, termin) == NULL)
 112                 destination[0] = '\0';
 113
 114         length = strlen(destination);
 115         if (length > 0 && destination[length - 1] != '\n')
 116         {
 117                 /* eat rest of the line */
 118                 char            buf[128];
 119                 int                     buflen;
 120
 121                 do
 122                 {
 123                         if (fgets(buf, sizeof(buf), termin) == NULL)
 124                                 break;
 125                         buflen = strlen(buf);
 126                 } while (buflen > 0 && buf[buflen - 1] != '\n');
 127         }
 128
 129         if (length > 0 && destination[length - 1] == '\n')
 130                 /* remove trailing newline */
 131                 destination[length - 1] = '\0';
 132
 133 #ifdef HAVE_TERMIOS_H
 134         if (!echo)
 135         {
 136                 tcsetattr(fileno(termin), TCSAFLUSH, &t_orig);
 137                 fputs("\n", termout);
 138                 fflush(termout);
 139         }
 140 #else
 141 #ifdef WIN32
 142         if (!echo)
 143         {
 144                 /* reset to the original console mode */
 145                 SetConsoleMode(t, *t_orig);
 146                 fputs("\n", termout);
 147                 fflush(termout);
 148                 free(t_orig);
 149         }
 150 #endif
 151 #endif
 152
 153         if (termin != stdin)
 154         {
 155                 fclose(termin);
 156                 fclose(termout);
 157         }
 158
 159         return destination;
 160 }