external/ibm-public/postfix/dist/src/util/argv.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      argv 3
   6 /* SUMMARY
   7 /*      string array utilities
   8 /* SYNOPSIS
   9 /*      #include <argv.h>
  10 /*
  11 /*      ARGV    *argv_alloc(len)
  12 /*      ssize_t len;
  13 /*
  14 /*      ARGV    *argv_free(argvp)
  15 /*      ARGV    *argvp;
  16 /*
  17 /*      void    argv_add(argvp, arg, ..., ARGV_END)
  18 /*      ARGV    *argvp;
  19 /*      char    *arg;
  20 /*
  21 /*      void    argv_addn(argvp, arg, arg_len, ..., ARGV_END)
  22 /*      ARGV    *argvp;
  23 /*      char    *arg;
  24 /*      ssize_t arg_len;
  25 /*
  26 /*      void    argv_terminate(argvp);
  27 /*      ARGV    *argvp;
  28 /*
  29 /*      void    argv_truncate(argvp, len);
  30 /*      ARGV    *argvp;
  31 /*      ssize_t len;
  32 /* DESCRIPTION
  33 /*      The functions in this module manipulate arrays of string
  34 /*      pointers. An ARGV structure contains the following members:
  35 /* .IP len
  36 /*      The length of the \fIargv\fR array member.
  37 /* .IP argc
  38 /*      The number of \fIargv\fR elements used.
  39 /* .IP argv
  40 /*      An array of pointers to null-terminated strings.
  41 /* .PP
  42 /*      argv_alloc() returns an empty string array of the requested
  43 /*      length. The result is ready for use by argv_add(). The array
  44 /*      is null terminated.
  45 /*
  46 /*      argv_add() copies zero or more strings and adds them to the
  47 /*      specified string array. The array is null terminated.
  48 /*      Terminate the argument list with a null pointer. The manifest
  49 /*      constant ARGV_END provides a convenient notation for this.
  50 /*
  51 /*      argv_addn() is like argv_add(), but each string is followed
  52 /*      by a string length argument.
  53 /*
  54 /*      argv_free() releases storage for a string array, and conveniently
  55 /*      returns a null pointer.
  56 /*
  57 /*      argv_terminate() null-terminates its string array argument.
  58 /*
  59 /*      argv_truncate() trucates its argument to the specified
  60 /*      number of entries, but does not reallocate memory. The
  61 /*      result is null-terminated.
  62 /* SEE ALSO
  63 /*      msg(3) diagnostics interface
  64 /* DIAGNOSTICS
  65 /*      Fatal errors: memory allocation problem.
  66 /* LICENSE
  67 /* .ad
  68 /* .fi
  69 /*      The Secure Mailer license must be distributed with this software.
  70 /* AUTHOR(S)
  71 /*      Wietse Venema
  72 /*      IBM T.J. Watson Research
  73 /*      P.O. Box 704
  74 /*      Yorktown Heights, NY 10598, USA
  75 /*--*/
  76
  77 /* System libraries. */
  78
  79 #include <sys_defs.h>
  80 #include <stdlib.h>                     /* 44BSD stdarg.h uses abort() */
  81 #include <stdarg.h>
  82 #include <string.h>
  83
  84 /* Application-specific. */
  85
  86 #include "mymalloc.h"
  87 #include "msg.h"
  88 #include "argv.h"
  89
  90 /* argv_free - destroy string array */
  91
  92 ARGV   *argv_free(ARGV *argvp)
  93 {
  94     char  **cpp;
  95
  96     for (cpp = argvp->argv; cpp < argvp->argv + argvp->argc; cpp++)
  97         myfree(*cpp);
  98     myfree((char *) argvp->argv);
  99     myfree((char *) argvp);
 100     return (0);
 101 }
 102
 103 /* argv_alloc - initialize string array */
 104
 105 ARGV   *argv_alloc(ssize_t len)
 106 {
 107     ARGV   *argvp;
 108     ssize_t sane_len;
 109
 110     /*
 111      * Make sure that always argvp->argc < argvp->len.
 112      */
 113     argvp = (ARGV *) mymalloc(sizeof(*argvp));
 114     argvp->len = 0;
 115     sane_len = (len < 2 ? 2 : len);
 116     argvp->argv = (char **) mymalloc((sane_len + 1) * sizeof(char *));
 117     argvp->len = sane_len;
 118     argvp->argc = 0;
 119     argvp->argv[0] = 0;
 120     return (argvp);
 121 }
 122
 123 /* argv_extend - extend array */
 124
 125 static void argv_extend(ARGV *argvp)
 126 {
 127     ssize_t new_len;
 128
 129     new_len = argvp->len * 2;
 130     argvp->argv = (char **)
 131         myrealloc((char *) argvp->argv, (new_len + 1) * sizeof(char *));
 132     argvp->len = new_len;
 133 }
 134
 135 /* argv_add - add string to vector */
 136
 137 void    argv_add(ARGV *argvp,...)
 138 {
 139     char   *arg;
 140     va_list ap;
 141
 142     /*
 143      * Make sure that always argvp->argc < argvp->len.
 144      */
 145 #define ARGV_SPACE_LEFT(a) ((a)->len - (a)->argc - 1)
 146
 147     va_start(ap, argvp);
 148     while ((arg = va_arg(ap, char *)) != 0) {
 149         if (ARGV_SPACE_LEFT(argvp) <= 0)
 150             argv_extend(argvp);
 151         argvp->argv[argvp->argc++] = mystrdup(arg);
 152     }
 153     va_end(ap);
 154     argvp->argv[argvp->argc] = 0;
 155 }
 156
 157 /* argv_addn - add string to vector */
 158
 159 void    argv_addn(ARGV *argvp,...)
 160 {
 161     char   *arg;
 162     ssize_t len;
 163     va_list ap;
 164
 165     /*
 166      * Make sure that always argvp->argc < argvp->len.
 167      */
 168     va_start(ap, argvp);
 169     while ((arg = va_arg(ap, char *)) != 0) {
 170         if ((len = va_arg(ap, ssize_t)) < 0)
 171             msg_panic("argv_addn: bad string length %ld", (long) len);
 172         if (ARGV_SPACE_LEFT(argvp) <= 0)
 173             argv_extend(argvp);
 174         argvp->argv[argvp->argc++] = mystrndup(arg, len);
 175     }
 176     va_end(ap);
 177     argvp->argv[argvp->argc] = 0;
 178 }
 179
 180 /* argv_terminate - terminate string array */
 181
 182 void    argv_terminate(ARGV *argvp)
 183 {
 184
 185     /*
 186      * Trust that argvp->argc < argvp->len.
 187      */
 188     argvp->argv[argvp->argc] = 0;
 189 }
 190
 191 /* argv_truncate - truncate string array */
 192
 193 void    argv_truncate(ARGV *argvp, ssize_t len)
 194 {
 195     char  **cpp;
 196
 197     /*
 198      * Sanity check.
 199      */
 200     if (len < 0)
 201         msg_panic("argv_truncate: bad length %ld", (long) len);
 202
 203     if (len < argvp->argc) {
 204         for (cpp = argvp->argv + len; cpp < argvp->argv + argvp->argc; cpp++)
 205             myfree(*cpp);
 206         argvp->argc = len;
 207         argvp->argv[argvp->argc] = 0;
 208     }
 209 }