newlib-cygwin/newlib/libc/posix/execvp.c

72 lines
1.3 KiB
C

#ifndef _NO_EXECVE
/* execvp.c */
/* This and the other exec*.c files in this directory require
the target to provide the _execve syscall. */
#include <_ansi.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#define PATH_DELIM ':'
/*
* Copy string, until c or <nul> is encountered.
* NUL-terminate the destination string (s1).
*/
static char *
strccpy (char *s1,
char *s2,
char c)
{
char *dest = s1;
while (*s2 && *s2 != c)
*s1++ = *s2++;
*s1 = 0;
return dest;
}
int
execvp (const char *file,
char * const argv[])
{
char *path = getenv ("PATH");
char buf[MAXNAMLEN];
/* If $PATH doesn't exist, just pass FILE on unchanged. */
if (!path)
return execv (file, argv);
/* If FILE contains a directory, don't search $PATH. */
if (strchr (file, '/')
)
return execv (file, argv);
while (*path)
{
strccpy (buf, path, PATH_DELIM);
/* An empty entry means the current directory. */
if (*buf != 0 && buf[strlen(buf) - 1] != '/')
strcat (buf, "/");
strcat (buf, file);
if (execv (buf, argv) == -1 && errno != ENOENT)
return -1;
while (*path && *path != PATH_DELIM)
path++;
if (*path == PATH_DELIM)
path++; /* skip over delim */
}
return -1;
}
#endif /* !_NO_EXECVE */