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/*******************************************************************/
/* slibtool: a skinny libtool implementation, written in C */
/* Copyright (C) 2016--2018 Z. Gilboa */
/* Released under the Standard MIT License; see COPYING.SLIBTOOL. */
/*******************************************************************/
#include <stdio.h>
#include <limits.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/wait.h>
#include <slibtool/slibtool.h>
#include "slibtool_spawn_impl.h"
static void slbt_dump_machine_child(
char * program,
int fd[2])
{
char * compiler;
char * argv[3];
close(fd[0]);
if ((compiler = strrchr(program,'/')))
compiler++;
else
compiler = program;
argv[0] = compiler;
argv[1] = "-dumpmachine";
argv[2] = 0;
if ((fd[0] = openat(AT_FDCWD,"/dev/null",O_RDONLY,0)) >= 0)
if (dup2(fd[0],0) == 0)
if (dup2(fd[1],1) == 1)
execvp(program,argv);
_exit(EXIT_FAILURE);
}
int slbt_dump_machine(
const char * compiler,
char * machine,
size_t buflen)
{
ssize_t ret;
pid_t pid;
pid_t rpid;
int code;
int fd[2];
char * mark;
char program[PATH_MAX];
/* setup */
if (!machine || !buflen || !--buflen) {
errno = EINVAL;
return -1;
}
if ((size_t)snprintf(program,sizeof(program),"%s",
compiler) >= sizeof(program))
return -1;
/* fork */
if (pipe(fd))
return -1;
if ((pid = fork()) < 0) {
close(fd[0]);
close(fd[1]);
return -1;
}
/* child */
if (pid == 0)
slbt_dump_machine_child(
program,
fd);
/* parent */
close(fd[1]);
mark = machine;
for (; buflen; ) {
ret = read(fd[0],mark,buflen);
while ((ret < 0) && (errno == EINTR))
ret = read(fd[0],mark,buflen);
if (ret > 0) {
buflen -= ret;
mark += ret;
} else if (ret == 0) {
close(fd[0]);
buflen = 0;
} else {
close(fd[0]);
return -1;
}
}
/* execve verification */
rpid = waitpid(
pid,
&code,
0);
if ((rpid != pid) || code) {
errno = ESTALE;
return -1;
}
/* newline verification */
if ((mark == machine) || (*--mark != '\n')) {
errno = ERANGE;
return -1;
}
*mark = 0;
/* portbld <--> unknown synonym? */
if ((mark = strstr(machine,"-portbld-")))
memcpy(mark,"-unknown",8);
/* all done */
return 0;
}
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