1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
|
/*******************************************************************/
/* slibtool: a skinny libtool implementation, written in C */
/* Copyright (C) 2016--2021 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;
}
|
