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#define STRERROR_OVERRIDE_IMPL 1
#include "strerror_override.h"
/*
* Override strerror() to get consistent output across platforms.
*/
static struct
{
int errno_value;
const char *errno_str;
} errno_list[] = {
/* clang-format off */
#define STRINGIFY(x) #x
#define ENTRY(x) {x, &STRINGIFY(undef_ ## x)[6]}
ENTRY(EPERM),
ENTRY(ENOENT),
ENTRY(ESRCH),
ENTRY(EINTR),
ENTRY(EIO),
ENTRY(ENXIO),
ENTRY(E2BIG),
#ifdef ENOEXEC
ENTRY(ENOEXEC),
#endif
ENTRY(EBADF),
ENTRY(ECHILD),
ENTRY(EDEADLK),
ENTRY(ENOMEM),
ENTRY(EACCES),
ENTRY(EFAULT),
#ifdef ENOTBLK
ENTRY(ENOTBLK),
#endif
ENTRY(EBUSY),
ENTRY(EEXIST),
ENTRY(EXDEV),
ENTRY(ENODEV),
ENTRY(ENOTDIR),
ENTRY(EISDIR),
ENTRY(EINVAL),
ENTRY(ENFILE),
ENTRY(EMFILE),
ENTRY(ENOTTY),
#ifdef ETXTBSY
ENTRY(ETXTBSY),
#endif
ENTRY(EFBIG),
ENTRY(ENOSPC),
ENTRY(ESPIPE),
ENTRY(EROFS),
ENTRY(EMLINK),
ENTRY(EPIPE),
ENTRY(EDOM),
ENTRY(ERANGE),
ENTRY(EAGAIN),
{ 0, (char *)0 }
};
/* clang-format on */
// Enabled during tests
static int _json_c_strerror_enable = 0;
extern char *getenv(const char *name); // Avoid including stdlib.h
#define PREFIX "ERRNO="
static char errno_buf[128] = PREFIX;
char *_json_c_strerror(int errno_in)
{
int start_idx;
char digbuf[20];
int ii, jj;
if (!_json_c_strerror_enable)
_json_c_strerror_enable = (getenv("_JSON_C_STRERROR_ENABLE") == NULL) ? -1 : 1;
if (_json_c_strerror_enable == -1)
return strerror(errno_in);
// Avoid standard functions, so we don't need to include any
// headers, or guess at signatures.
for (ii = 0; errno_list[ii].errno_str != (char *)0; ii++)
{
const char *errno_str = errno_list[ii].errno_str;
if (errno_list[ii].errno_value != errno_in)
continue;
for (start_idx = sizeof(PREFIX) - 1, jj = 0; errno_str[jj] != '\0';
jj++, start_idx++)
{
errno_buf[start_idx] = errno_str[jj];
}
errno_buf[start_idx] = '\0';
return errno_buf;
}
// It's not one of the known errno values, return the numeric value.
for (ii = 0; errno_in >= 10; errno_in /= 10, ii++)
{
digbuf[ii] = "0123456789"[(errno_in % 10)];
}
digbuf[ii] = "0123456789"[(errno_in % 10)];
// Reverse the digits
for (start_idx = sizeof(PREFIX) - 1; ii >= 0; ii--, start_idx++)
{
errno_buf[start_idx] = digbuf[ii];
}
errno_buf[start_idx] = '\0';
return errno_buf;
}