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#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/stat.h>
#include <errno.h>
#if HAVE_FCNTL_H
#include <fcntl.h>
#endif
#include "libhdr.h"
#define STDIN 0
#define STDOUT 1
#define READ 0
#define WRITE 1
static pid_t childpid = 0;
static void dupto (const int from,const int to,const char *msg)
{
int err;
if(from!=to) {
if(errno) perror("aa:");
err=close(to);
if (err<0 && errno != EBADF) {
perror("dupto(): Cannot close file descriptor");
exit(EXIT_FAILURE);
}
if(errno) perror("AA:");
err=dup(from);
if(errno) perror("BB:");
if (err!=to) {
(void)fprintf(stderr,"dupto(): Cannot dup %s\n",msg);
exit(EXIT_FAILURE);
}
if(close(from)<0) {
(void)fprintf(stderr,"dupto(): cannot close file descriptor\n");
exit(EXIT_FAILURE);
}
if(errno) perror("CC:");
}
}
int child_open1(const int read_flag,const char *fname,const char *filterprog,const char *arg)
{
int ppipe[2]={-1,-1},fd= -1,fd1;
struct stat sbuf;
if(!fname) return fd;
if(read_flag==READ) if(stat(fname,&sbuf)) return fd;
if(pipe(ppipe)<0) {
(void)fprintf(stderr,"child_open(): Can't open pipe\n");
return fd;
}
childpid=fork();
if(childpid<0) {
(void)fprintf(stderr, "child_open(): cannot fork\n");
return fd;
}
if(childpid>0) {
if(read_flag==READ) {
fd=ppipe[READ];
if(close(ppipe[WRITE])<0) {
(void)fprintf(stderr, "child_open(): cannot close pipe\n");
exit(EXIT_FAILURE);
}
} else {
fd=ppipe[WRITE];
if(close(ppipe[READ])<0) {
(void)fprintf(stderr, "child_open(): cannot close pipe\n");
exit(EXIT_FAILURE);
}
}
} else {
if(read_flag==READ) {
dupto(ppipe[WRITE], STDOUT,"(child) pipr to stdout");
if(close(ppipe[READ])<0) {
(void)fprintf(stderr, "child_open(): cannot close pipe\n");
exit(EXIT_FAILURE);
}
if(fname) {
fd1=open(fname,O_RDONLY,0666);
if(fd1<0) {
(void)fprintf(stderr, "child_open(): cannot open file %s\n",fname);
exit(EXIT_FAILURE);
}
dupto(fd1,STDIN,"file to stdin");
}
} else {
dupto (ppipe[READ], STDIN, "(child) pipe to stdin");
if(close(ppipe[WRITE])<0) {
(void)fprintf(stderr, "child_open(): cannot close pipe\n");
exit(EXIT_FAILURE);
}
if(fname) {
fd1=creat(fname,0666);
if(fd1<0) {
(void)fprintf(stderr, "child_open(): cannot open file %s\n",fname);
exit(EXIT_FAILURE);
}
dupto(fd1,STDOUT,"file to stdout");
}
}
if(read_flag==READ) (void)execlp(filterprog,filterprog,arg,(char *)0);
else (void)execlp(filterprog,filterprog,arg,(char *) 0);
(void)fprintf(stderr, "child_open(): cannot exec %s\n",filterprog);
_exit(EXIT_FAILURE);
}
return fd;
}
int child_open(const int read_flag,const char *fname,const char *filterprog)
{
int fd;
if(read_flag==READ) fd=child_open1(read_flag,fname,filterprog,"-d");
else fd=child_open1(read_flag,fname,filterprog,0);
return fd;
}
#if !HAVE_POPEN
FILE *popen(const char *command,const char *type)
{
int ppipe[2]={-1,-1},read_flag,fd;
FILE *fptr=0;
if(!command) return fptr;
if(!strcmp("r",type)) read_flag=READ;
else if(!strcmp("w",type)) read_flag=WRITE;
else return fptr;
if(pipe(ppipe)<0) {
(void)fprintf(stderr,"lk_popen(): Can't open pipe\n");
return fptr;
}
childpid=fork();
if(childpid<0) {
(void)fprintf(stderr, "lk_popen(): cannot fork\n");
return fptr;
}
if(childpid>0) {
if (read_flag==READ) {
fd = ppipe[READ];
if(close(ppipe[WRITE])<0) {
(void)fprintf(stderr, "lk_popen(): cannot close pipe\n");
exit(EXIT_FAILURE);
}
} else {
fd = ppipe[WRITE];
if(close(ppipe[READ])<0) {
(void)fprintf(stderr, "lk_popen(): cannot close pipe\n");
exit(EXIT_FAILURE);
}
}
fptr=fdopen(fd,type);
if(!fptr) {
(void)fprintf(stderr, "lk_popen(): fdopen() failed\n");
exit(EXIT_FAILURE);
}
} else {
if(read_flag==READ) {
dupto (ppipe[WRITE], STDOUT, "(child) pipe to stdout");
if(close(ppipe[READ])<0) {
(void)fprintf(stderr, "lk_popen(): cannot close pipe\n");
exit(EXIT_FAILURE);
}
} else {
dupto (ppipe[READ], STDIN, "(child) pipe to stdin");
if(close(ppipe[WRITE])<0) {
(void)fprintf(stderr, "lk_popen(): cannot close pipe\n");
exit(EXIT_FAILURE);
}
}
(int)execl("/bin/sh","sh","-c",command,(char *)0);
(void)fprintf(stderr, "lk_popen(): cannot exec %s\n",command);
_exit(EXIT_FAILURE);
}
return fptr;
}
#endif
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