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

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      sys_compat 3
   6 /* SUMMARY
   7 /*      compatibility routines
   8 /* SYNOPSIS
   9 /*      #include <sys_defs.h>
  10 /*
  11 /*      void    closefrom(int lowfd)
  12 /*      int     lowfd;
  13 /*
  14 /*      const char *strerror(err)
  15 /*      int     err;
  16 /*
  17 /*      int     setenv(name, value, clobber)
  18 /*      const char *name;
  19 /*      const char *value;
  20 /*      int     clobber;
  21 /*
  22 /*      int     seteuid(euid)
  23 /*      uid_t   euid;
  24 /*
  25 /*      int     setegid(egid)
  26 /*      gid_t   euid;
  27 /*
  28 /*      int     mkfifo(path, mode)
  29 /*      char    *path;
  30 /*      int     mode;
  31 /*
  32 /*      int     waitpid(pid, statusp, options)
  33 /*      int     pid;
  34 /*      WAIT_STATUS_T *statusp;
  35 /*      int     options;
  36 /*
  37 /*      int     setsid()
  38 /*
  39 /*      void    dup2_pass_on_exec(int oldd, int newd)
  40 /*
  41 /*      char    *inet_ntop(af, src, dst, size)
  42 /*      int     af;
  43 /*      const void *src;
  44 /*      char    *dst;
  45 /*      size_t  size;
  46 /*
  47 /*      int     inet_pton(af, src, dst)
  48 /*      int     af;
  49 /*      const char *src;
  50 /*      void    *dst;
  51 /* DESCRIPTION
  52 /*      These routines are compiled for platforms that lack the functionality
  53 /*      or that have broken versions that we prefer to stay away from.
  54 /* LICENSE
  55 /* .ad
  56 /* .fi
  57 /*      The Secure Mailer license must be distributed with this software.
  58 /* AUTHOR(S)
  59 /*      Wietse Venema
  60 /*      IBM T.J. Watson Research
  61 /*      P.O. Box 704
  62 /*      Yorktown Heights, NY 10598, USA
  63 /*--*/
  64
  65 /* System library. */
  66
  67 #include "sys_defs.h"
  68
  69  /*
  70   * ANSI strerror() emulation
  71   */
  72 #ifdef MISSING_STRERROR
  73
  74 extern int errno;
  75 extern char *sys_errlist[];
  76 extern int sys_nerr;
  77
  78 #include <vstring.h>
  79
  80 /* strerror - print text corresponding to error */
  81
  82 const char *strerror(int err)
  83 {
  84     static VSTRING *buf;
  85
  86     if (err < 0 || err >= sys_nerr) {
  87         if (buf == 0)
  88             buf = vstring_alloc(10);
  89         vstring_sprintf(buf, "Unknown error %d", err);
  90         return (vstring_str(buf));
  91     } else {
  92         return (sys_errlist[errno]);
  93     }
  94 }
  95
  96 #endif
  97
  98  /*
  99   * setenv() emulation on top of putenv().
 100   */
 101 #ifdef MISSING_SETENV
 102
 103 #include <stdio.h>
 104 #include <string.h>
 105 #include <stdlib.h>
 106
 107 /* setenv - update or insert environment (name,value) pair */
 108
 109 int     setenv(const char *name, const char *value, int clobber)
 110 {
 111     char   *cp;
 112
 113     if (clobber == 0 && getenv(name) != 0)
 114         return (0);
 115     if ((cp = malloc(strlen(name) + strlen(value) + 2)) == 0)
 116         return (1);
 117     sprintf(cp, "%s=%s", name, value);
 118     return (putenv(cp));
 119 }
 120
 121 #endif
 122
 123  /*
 124   * seteuid() and setegid() emulation, the HP-UX way
 125   */
 126 #ifdef MISSING_SETEUID
 127 #ifdef HAVE_SETRESUID
 128 #include <unistd.h>
 129
 130 int     seteuid(uid_t euid)
 131 {
 132     return setresuid(-1, euid, -1);
 133 }
 134
 135 #else
 136 #error MISSING_SETEUID
 137 #endif
 138
 139 #endif
 140
 141 #ifdef MISSING_SETEGID
 142 #ifdef HAVE_SETRESGID
 143 #include <unistd.h>
 144
 145 int     setegid(gid_t egid)
 146 {
 147     return setresgid(-1, egid, -1);
 148 }
 149
 150 #else
 151 #error MISSING_SETEGID
 152 #endif
 153
 154 #endif
 155
 156  /*
 157   * mkfifo() emulation - requires superuser privileges
 158   */
 159 #ifdef MISSING_MKFIFO
 160
 161 #include <sys/stat.h>
 162
 163 int     mkfifo(char *path, int mode)
 164 {
 165     return mknod(path, (mode & ~_S_IFMT) | _S_IFIFO, 0);
 166 }
 167
 168 #endif
 169
 170  /*
 171   * waitpid() emulation on top of Berkeley UNIX wait4()
 172   */
 173 #ifdef MISSING_WAITPID
 174 #ifdef HAS_WAIT4
 175
 176 #include <sys/wait.h>
 177 #include <errno.h>
 178
 179 int     waitpid(int pid, WAIT_STATUS_T *status, int options)
 180 {
 181     if (pid == -1)
 182         pid = 0;
 183     return wait4(pid, status, options, (struct rusage *) 0);
 184 }
 185
 186 #else
 187 #error MISSING_WAITPID
 188 #endif
 189
 190 #endif
 191
 192  /*
 193   * setsid() emulation, the Berkeley UNIX way
 194   */
 195 #ifdef MISSING_SETSID
 196
 197 #include <sys/ioctl.h>
 198 #include <unistd.h>
 199 #include <fcntl.h>
 200 #include <errno.h>
 201
 202 #ifdef TIOCNOTTY
 203
 204 #include <msg.h>
 205
 206 int     setsid(void)
 207 {
 208     int     p = getpid();
 209     int     fd;
 210
 211     if (setpgrp(p, p))
 212         return -1;
 213
 214     fd = open("/dev/tty", O_RDONLY, 0);
 215     if (fd >= 0 || errno != ENXIO) {
 216         if (fd < 0) {
 217             msg_warn("open /dev/tty: %m");
 218             return -1;
 219         }
 220         if (ioctl(fd, TIOCNOTTY, 0)) {
 221             msg_warn("ioctl TIOCNOTTY: %m");
 222             return -1;
 223         }
 224         close(fd);
 225     }
 226     return 0;
 227 }
 228
 229 #else
 230 #error MISSING_SETSID
 231 #endif
 232
 233 #endif
 234
 235  /*
 236   * dup2_pass_on_exec() - dup2() and clear close-on-exec flag on the result
 237   */
 238 #ifdef DUP2_DUPS_CLOSE_ON_EXEC
 239
 240 #include "iostuff.h"
 241
 242 int     dup2_pass_on_exec(int oldd, int newd)
 243 {
 244     int     res;
 245
 246     if ((res = dup2(oldd, newd)) >= 0)
 247         close_on_exec(newd, PASS_ON_EXEC);
 248
 249     return res;
 250 }
 251
 252 #endif
 253
 254 #ifndef HAS_CLOSEFROM
 255
 256 #include <unistd.h>
 257 #include <errno.h>
 258 #include <iostuff.h>
 259
 260 /* closefrom() - closes all file descriptors from the given one up */
 261
 262 int     closefrom(int lowfd)
 263 {
 264     int     fd_limit = open_limit(0);
 265     int     fd;
 266
 267     /*
 268      * lowfrom does not have an easy to determine upper limit. A process may
 269      * have files open that were inherited from a parent process with a less
 270      * restrictive resource limit.
 271      */
 272     if (lowfd < 0) {
 273         errno = EBADF;
 274         return (-1);
 275     }
 276     if (fd_limit > 500)
 277         fd_limit = 500;
 278     for (fd = lowfd; fd < fd_limit; fd++)
 279         (void) close(fd);
 280
 281     return (0);
 282 }
 283
 284 #endif
 285
 286 #ifdef MISSING_INET_NTOP
 287
 288 #include <sys/types.h>
 289 #include <sys/socket.h>
 290 #include <netinet/in.h>
 291 #include <arpa/inet.h>
 292 #include <stdio.h>
 293 #include <string.h>
 294 #include <errno.h>
 295
 296 /* inet_ntop - convert binary address to printable address */
 297
 298 const char *inet_ntop(int af, const void *src, char *dst, size_t size)
 299 {
 300     const unsigned char *addr;
 301     char    buffer[sizeof("255.255.255.255")];
 302     int     len;
 303
 304     if (af != AF_INET) {
 305         errno = EAFNOSUPPORT;
 306         return (0);
 307     }
 308     addr = (const unsigned char *) src;
 309 #if (CHAR_BIT > 8)
 310     sprintf(buffer, "%d.%d.%d.%d", addr[0] & 0xff,
 311             addr[1] & 0xff, addr[2] & 0xff, addr[3] & 0xff);
 312 #else
 313     sprintf(buffer, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
 314 #endif
 315     if ((len = strlen(buffer)) >= size) {
 316         errno = ENOSPC;
 317         return (0);
 318     } else {
 319         memcpy(dst, buffer, len + 1);
 320         return (dst);
 321     }
 322 }
 323
 324 #endif
 325
 326 #ifdef MISSING_INET_PTON
 327
 328 #include <sys/types.h>
 329 #include <sys/socket.h>
 330 #include <netinet/in.h>
 331 #include <arpa/inet.h>
 332 #include <string.h>
 333 #include <errno.h>
 334
 335 #ifndef INADDR_NONE
 336 #define INADDR_NONE 0xffffffff
 337 #endif
 338
 339 /* inet_pton - convert printable address to binary address */
 340
 341 int     inet_pton(int af, const char *src, void *dst)
 342 {
 343     struct in_addr addr;
 344
 345     /*
 346      * inet_addr() accepts a wider range of input formats than inet_pton();
 347      * the former accepts 1-, 2-, or 3-part dotted addresses, while the
 348      * latter requires dotted quad form.
 349      */
 350     if (af != AF_INET) {
 351         errno = EAFNOSUPPORT;
 352         return (-1);
 353     } else if ((addr.s_addr = inet_addr(src)) == INADDR_NONE
 354                && strcmp(src, "255.255.255.255") != 0) {
 355         return (0);
 356     } else {
 357         memcpy(dst, (char *) &addr, sizeof(addr));
 358         return (1);
 359     }
 360 }
 361
 362 #endif