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/*++
/* NAME
/* sys_compat 3
/* SUMMARY
/* compatibility routines
/* SYNOPSIS
/* #include <sys_defs.h>
/*
/* void closefrom(int lowfd)
/* int lowfd;
/*
/* const char *strerror(err)
/* int err;
/*
/* int setenv(name, value, clobber)
/* const char *name;
/* const char *value;
/* int clobber;
/*
/* int unsetenv(name)
/* const char *name;
/*
/* int seteuid(euid)
/* uid_t euid;
/*
/* int setegid(egid)
/* gid_t euid;
/*
/* int mkfifo(path, mode)
/* char *path;
/* int mode;
/*
/* int waitpid(pid, statusp, options)
/* int pid;
/* WAIT_STATUS_T *statusp;
/* int options;
/*
/* int setsid()
/*
/* void dup2_pass_on_exec(int oldd, int newd)
/*
/* char *inet_ntop(af, src, dst, size)
/* int af;
/* const void *src;
/* char *dst;
/* SOCKADDR_SIZE size;
/*
/* int inet_pton(af, src, dst)
/* int af;
/* const char *src;
/* void *dst;
/* DESCRIPTION
/* These routines are compiled for platforms that lack the functionality
/* or that have broken versions that we prefer to stay away from.
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*--*/
/* System library. */
#include "sys_defs.h"
/*
* ANSI strerror() emulation
*/
#ifdef MISSING_STRERROR
extern int errno;
extern char *sys_errlist[];
extern int sys_nerr;
#include <vstring.h>
/* strerror - print text corresponding to error */
const char *strerror(int err)
{
static VSTRING *buf;
if (err < 0 || err >= sys_nerr) {
if (buf == 0)
buf = vstring_alloc(10);
vstring_sprintf(buf, "Unknown error %d", err);
return (vstring_str(buf));
} else {
return (sys_errlist[errno]);
}
}
#endif
/*
* setenv() emulation on top of putenv().
*/
#ifdef MISSING_SETENV
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
/* setenv - update or insert environment (name,value) pair */
int setenv(const char *name, const char *value, int clobber)
{
char *cp;
if (clobber == 0 && getenv(name) != 0)
return (0);
if ((cp = malloc(strlen(name) + strlen(value) + 2)) == 0)
return (1);
sprintf(cp, "%s=%s", name, value);
return (putenv(cp));
}
/* unsetenv - remove all instances of the name */
int unsetenv(const char *name)
{
extern char **environ;
ssize_t name_len = strlen(name);
char **src_pp;
char **dst_pp;
for (dst_pp = src_pp = environ; *src_pp; src_pp++, dst_pp++) {
if (strncmp(*src_pp, name, name_len) == 0
&& *(*src_pp + name_len) == '=') {
dst_pp--;
} else if (dst_pp != src_pp) {
*dst_pp = *src_pp;
}
}
*dst_pp = 0;
return (0);
}
#endif
/*
* seteuid() and setegid() emulation, the HP-UX way
*/
#ifdef MISSING_SETEUID
#ifdef HAVE_SETRESUID
#include <unistd.h>
int seteuid(uid_t euid)
{
return setresuid(-1, euid, -1);
}
#else
#error MISSING_SETEUID
#endif
#endif
#ifdef MISSING_SETEGID
#ifdef HAVE_SETRESGID
#include <unistd.h>
int setegid(gid_t egid)
{
return setresgid(-1, egid, -1);
}
#else
#error MISSING_SETEGID
#endif
#endif
/*
* mkfifo() emulation - requires superuser privileges
*/
#ifdef MISSING_MKFIFO
#include <sys/stat.h>
int mkfifo(char *path, int mode)
{
return mknod(path, (mode & ~_S_IFMT) | _S_IFIFO, 0);
}
#endif
/*
* waitpid() emulation on top of Berkeley UNIX wait4()
*/
#ifdef MISSING_WAITPID
#ifdef HAS_WAIT4
#include <sys/wait.h>
#include <errno.h>
int waitpid(int pid, WAIT_STATUS_T *status, int options)
{
if (pid == -1)
pid = 0;
return wait4(pid, status, options, (struct rusage *) 0);
}
#else
#error MISSING_WAITPID
#endif
#endif
/*
* setsid() emulation, the Berkeley UNIX way
*/
#ifdef MISSING_SETSID
#include <sys/ioctl.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#ifdef TIOCNOTTY
#include <msg.h>
int setsid(void)
{
int p = getpid();
int fd;
if (setpgrp(p, p))
return -1;
fd = open("/dev/tty", O_RDONLY, 0);
if (fd >= 0 || errno != ENXIO) {
if (fd < 0) {
msg_warn("open /dev/tty: %m");
return -1;
}
if (ioctl(fd, TIOCNOTTY, 0)) {
msg_warn("ioctl TIOCNOTTY: %m");
return -1;
}
close(fd);
}
return 0;
}
#else
#error MISSING_SETSID
#endif
#endif
/*
* dup2_pass_on_exec() - dup2() and clear close-on-exec flag on the result
*/
#ifdef DUP2_DUPS_CLOSE_ON_EXEC
#include "iostuff.h"
int dup2_pass_on_exec(int oldd, int newd)
{
int res;
if ((res = dup2(oldd, newd)) >= 0)
close_on_exec(newd, PASS_ON_EXEC);
return res;
}
#endif
#ifndef HAS_CLOSEFROM
#include <unistd.h>
#include <errno.h>
#include <iostuff.h>
/* closefrom() - closes all file descriptors from the given one up */
int closefrom(int lowfd)
{
int fd_limit = open_limit(0);
int fd;
/*
* lowfrom does not have an easy to determine upper limit. A process may
* have files open that were inherited from a parent process with a less
* restrictive resource limit.
*/
if (lowfd < 0) {
errno = EBADF;
return (-1);
}
if (fd_limit > 500)
fd_limit = 500;
for (fd = lowfd; fd < fd_limit; fd++)
(void) close(fd);
return (0);
}
#endif
#ifdef MISSING_INET_NTOP
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
/* inet_ntop - convert binary address to printable address */
const char *inet_ntop(int af, const void *src, char *dst, SOCKADDR_SIZE size)
{
const unsigned char *addr;
char buffer[sizeof("255.255.255.255")];
int len;
if (af != AF_INET) {
errno = EAFNOSUPPORT;
return (0);
}
addr = (const unsigned char *) src;
#if (CHAR_BIT > 8)
sprintf(buffer, "%d.%d.%d.%d", addr[0] & 0xff,
addr[1] & 0xff, addr[2] & 0xff, addr[3] & 0xff);
#else
sprintf(buffer, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
#endif
if ((len = strlen(buffer)) >= size) {
errno = ENOSPC;
return (0);
} else {
memcpy(dst, buffer, len + 1);
return (dst);
}
}
#endif
#ifdef MISSING_INET_PTON
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <errno.h>
#ifndef INADDR_NONE
#define INADDR_NONE 0xffffffff
#endif
/* inet_pton - convert printable address to binary address */
int inet_pton(int af, const char *src, void *dst)
{
struct in_addr addr;
/*
* inet_addr() accepts a wider range of input formats than inet_pton();
* the former accepts 1-, 2-, or 3-part dotted addresses, while the
* latter requires dotted quad form.
*/
if (af != AF_INET) {
errno = EAFNOSUPPORT;
return (-1);
} else if ((addr.s_addr = inet_addr(src)) == INADDR_NONE
&& strcmp(src, "255.255.255.255") != 0) {
return (0);
} else {
memcpy(dst, (void *) &addr, sizeof(addr));
return (1);
}
}
#endif