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/* This is part of pure_libc (a project related to ViewOS and Virtual Square)
*
* exec.c: exec to execve conversion
*
* Copyright 2006-2017 Renzo Davoli University of Bologna - Italy
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* The GNU C Library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with the GNU C Library; if not, write to the Free
* Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
#include <config.h>
#include <unistd.h>
#include <assert.h>
#include <stdarg.h>
#include <alloca.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <limits.h>
#define _PURE_DEFAULT_PATH "/bin:/usr/bin"
int execl(const char *path, const char *arg, ...){
va_list ap;
int argc=2,i;
va_start(ap,arg);
while(va_arg(ap,char *) != 0)
argc++;
va_end(ap);
char *argv[argc];
argv[0]=(char *)arg;
va_start(ap,arg);
for (i=1;i<argc;i++)
argv[i]=va_arg(ap,char*);
argv[i]=(char *) 0;
va_end(ap);
return execve(path,argv,environ);
}
int execlp(const char *file, const char *arg, ...){
va_list ap;
int argc=2,i;
va_start(ap,arg);
while(va_arg(ap,char *) != 0)
argc++;
va_end(ap);
char *argv[argc];
argv[0]=(char *)arg;
va_start(ap,arg);
for (i=1;i<argc;i++)
argv[i]=va_arg(ap,char*);
va_end(ap);
return execvp(file,argv);
}
int execle(const char *path, const char *arg , .../*, char * const envp[]*/){
va_list ap;
int argc=2,i;
char **envp;
va_start(ap,arg);
while(va_arg(ap,char *) != 0)
argc++;
va_end(ap);
char *argv[argc];
argv[0]=(char *)arg;
va_start(ap,arg);
for (i=1;i<argc;i++)
argv[i]=va_arg(ap,char*);
envp=va_arg(ap,char**);
va_end(ap);
return execve(path,argv,envp);
}
int execv(const char *path, char *const argv[]){
return execve(path,argv,environ);
}
int execvp(const char *file, char *const argv[]){
if(strchr(file,'/') != NULL)
return execve(file,argv,environ);
else {
char *path;
char *envpath;
char *pathelem;
char buf[PATH_MAX];
if ((envpath=getenv("PATH")) == NULL)
envpath=_PURE_DEFAULT_PATH;
path=strdup(envpath);
while((pathelem=strsep(&path,":")) != NULL){
if (*pathelem != 0) {
register int i,j;
for (i=0; i<PATH_MAX && pathelem[i]; i++)
buf[i]=pathelem[i];
if(buf[i-1] != '/' && i<PATH_MAX)
buf[i++]='/';
for (j=0; i<PATH_MAX && file[j]; j++,i++)
buf[i]=file[j];
buf[i]=0;
if (execve(buf,argv,environ)<0 &&
((errno != ENOENT) && (errno != ENOTDIR) && (errno != EACCES))) {
free(path);
return -1;
}
}
}
free(path);
errno = ENOENT;
return -1;
}
}
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