1 /* $OpenBSD: strerror_r.c,v 1.6 2005/08/08 08:05:37 espie Exp $ */
2 /* Public Domain <marc@snafu.org> */
3
4 // G++ automatically defines _GNU_SOURCE, which then means that <string.h>
5 // gives us the GNU variant.
6 #undef _GNU_SOURCE
7
8 #include <string.h>
9
10 #include <errno.h>
11 #include <limits.h>
12 #include <signal.h>
13 #include <stdio.h>
14
15 #include <async_safe/log.h>
16
17 #include "private/ErrnoRestorer.h"
18
19 struct Pair {
20 int code;
21 const char* msg;
22 };
23
__code_string_lookup(const Pair * strings,int code)24 static const char* __code_string_lookup(const Pair* strings, int code) {
25 for (size_t i = 0; strings[i].msg != NULL; ++i) {
26 if (strings[i].code == code) {
27 return strings[i].msg;
28 }
29 }
30 return NULL;
31 }
32
33 static const Pair _sys_error_strings[] = {
34 #define __BIONIC_ERRDEF(x,y,z) { x, z },
35 #include "private/bionic_errdefs.h"
36 { 0, NULL }
37 };
38
__strerror_lookup(int error_number)39 extern "C" __LIBC_HIDDEN__ const char* __strerror_lookup(int error_number) {
40 return __code_string_lookup(_sys_error_strings, error_number);
41 }
42
43 static const Pair _sys_signal_strings[] = {
44 #define __BIONIC_SIGDEF(signal_number, signal_description) { signal_number, signal_description },
45 #include "private/bionic_sigdefs.h"
46 { 0, NULL }
47 };
48
__strsignal_lookup(int signal_number)49 extern "C" __LIBC_HIDDEN__ const char* __strsignal_lookup(int signal_number) {
50 return __code_string_lookup(_sys_signal_strings, signal_number);
51 }
52
strerror_r(int error_number,char * buf,size_t buf_len)53 int strerror_r(int error_number, char* buf, size_t buf_len) {
54 ErrnoRestorer errno_restorer;
55 size_t length;
56
57 const char* error_name = __strerror_lookup(error_number);
58 if (error_name != NULL) {
59 length = strlcpy(buf, error_name, buf_len);
60 } else {
61 length = async_safe_format_buffer(buf, buf_len, "Unknown error %d", error_number);
62 }
63 if (length >= buf_len) {
64 errno_restorer.override(ERANGE);
65 return -1;
66 }
67
68 return 0;
69 }
70
__gnu_strerror_r(int error_number,char * buf,size_t buf_len)71 extern "C" char* __gnu_strerror_r(int error_number, char* buf, size_t buf_len) {
72 ErrnoRestorer errno_restorer; // The glibc strerror_r doesn't set errno if it truncates...
73 strerror_r(error_number, buf, buf_len);
74 return buf; // ...and just returns whatever fit.
75 }
76
__strsignal(int signal_number,char * buf,size_t buf_len)77 extern "C" __LIBC_HIDDEN__ const char* __strsignal(int signal_number, char* buf, size_t buf_len) {
78 const char* signal_name = __strsignal_lookup(signal_number);
79 if (signal_name != NULL) {
80 return signal_name;
81 }
82
83 const char* prefix = "Unknown";
84 if (signal_number >= SIGRTMIN && signal_number <= SIGRTMAX) {
85 prefix = "Real-time";
86 signal_number -= SIGRTMIN;
87 }
88 size_t length = snprintf(buf, buf_len, "%s signal %d", prefix, signal_number);
89 if (length >= buf_len) {
90 return NULL;
91 }
92 return buf;
93 }
94