void _sprintf(char *s, const char *fmt, ...)
{
va_list va;
_sprintf_dst = s;
va_start(va, fmt);
_vfprintf(_sprintf_write, fmt, va);
va_end(va);
*_sprintf_dst = '\0';
}
static void nprintf(char *errcode, ...)
{
va_list a;
char s[80];
char *p = s;
start_string_char(errcode);
/*
* Convert error code into a string so that it can be printed. I expect
* all strings used to be less than 80 characters long.
*/
while ((*p++ = fetch_string_char()) != 0);
va_start(a, errcode);
_vfprintf(stderr, s, a);
va_end(a);
}
static void errprintf(char *s, ...)
{
va_list a;
va_start(a, s);
_vfprintf(stderr, s, a);
va_end(a);
#ifndef NO_LISTING_OUTPUT
if (listingstream != NULL)
{ check_error_buffer();
va_start(a, s);
errsavep += (_vsprintf(&errsaves[errsavep], s, a),
strlen(&errsaves[errsavep]));
va_end(a);
}
#endif
}
/*
* Logs an DEBUG message on stdout
*/
static void debug(const char * format, ...) {
va_list args;
va_start(args,format);
_vfprintf(stdout,"DEBUG",format,args);
va_end(args);
}
/*
* Logs an ERROR message on stderr
*/
static void error(const char * format, ...) {
va_list args;
va_start(args,format);
_vfprintf(stderr,"ERROR",format,args);
va_end(args);
}
/*
* Logs an INFO message on stdout
*/
static void info(const char * format, ...) {
va_list args;
va_start(args,format);
_vfprintf(stdout,"INFO",format,args);
va_end(args);
}
int com_vfprintf(const char *fncName, FILE *stream, const char *format, va_list ap) {
// Get libc syscall function pointer & offset in image
libc_func(vfprintf, int, FILE *, const char *, va_list);
if (plr_checkInsidePLR()) {
// If already inside PLR code, just call original syscall & return
return _vfprintf(stream, format, ap);
} else {
plr_setInsidePLR();
int fn = fileno(stream);
if (plrlogIsEnabled(LOG_SYSCALL)) {
char *formatFmt = str_expandEscapes(format);
plrlog(LOG_SYSCALL, "[%d:%s] Fileno %d, format '%s'\n", getpid(), fncName, fn, formatFmt);
free(formatFmt);
}
// Use vasprintf to compute final string so that arguments can be checked
// in addition to format
va_list apCopy;
va_copy(apCopy, ap);
char *resStr;
int vasRet = vasprintf(&resStr, format, apCopy);
va_end(apCopy);
if (plrlogIsEnabled(LOG_DEBUG)) {
char *resStrFmt = str_expandEscapes(resStr);
plrlog(LOG_DEBUG, "[%d:%s] Str = '%s'\n", getpid(), fncName, resStrFmt);
free(resStrFmt);
}
syscallArgs_t args = {
.addr = _off_vfprintf,
.arg[0] = crc32(0, fncName, strlen(fncName)),
.arg[1] = fn,
.arg[2] = ((vasRet) ? crc32(0, resStr, strlen(resStr)) : 0),
};
plr_checkSyscallArgs(&args);
if (vasRet != -1) {
free(resStr);
}
// Nested function actually performed by master process only
ssize_t ret;
int masterAct() {
// Call original libc function
ret = _vfprintf(stream, format, ap);
// Store return value in shared memory for slave processes
printfShmData_t shmDat = { .err = errno, .ret = ret };
plr_copyToShm(&shmDat, sizeof(shmDat), 0);
return 0;
}
// All processes call plr_masterAction() to synchronize at this point
plr_masterAction(masterAct);
if (!plr_isMasterProcess()) {
// Slaves copy return values from shared memory
printfShmData_t shmDat;
plr_copyFromShm(&shmDat, sizeof(shmDat), 0);
// Return same value & errno as master
ret = shmDat.ret;
errno = shmDat.err;
}
plr_clearInsidePLR();
return ret;
}
}
