uint64_t util_rndGet(uint64_t min, uint64_t max)
{
if (min > max) {
LOG_F("min:%" PRIu64 " > max:%" PRIu64, min, max);
}
if (util_urandomFd == -1) {
if ((util_urandomFd = open("/dev/urandom", O_RDONLY)) == -1) {
PLOG_F("Couldn't open /dev/urandom for writing");
}
}
if (rndIni == false) {
if (files_readFromFd(util_urandomFd, (uint8_t *) & rndX, sizeof(rndX)) == false) {
PLOG_F("Couldn't read '%zu' bytes from /dev/urandom", sizeof(rndX));
}
rndIni = true;
}
/* MMIX LCG PRNG */
static const uint64_t a = 6364136223846793005ULL;
static const uint64_t c = 1442695040888963407ULL;
rndX = (a * rndX + c);
return ((rndX % (max - min + 1)) + min);
}
ssize_t files_readFileToBufMax(char *fileName, uint8_t * buf, size_t fileMaxSz)
{
int fd = open(fileName, O_RDONLY);
if (fd == -1) {
PLOG_W("Couldn't open '%s' for R/O", fileName);
return -1;
}
defer {
close(fd);
};
ssize_t readSz = files_readFromFd(fd, buf, fileMaxSz);
if (readSz < 0) {
LOG_W("Couldn't read '%s' to a buf", fileName);
return -1;
}
LOG_D("Read '%zu' bytes from '%s'", readSz, fileName);
return readSz;
}
/*
* dstExists argument can be used by caller for cases where existing destination
* file requires special handling (e.g. save unique crashes)
*/
bool files_copyFile(const char *source, const char *destination, bool * dstExists)
{
if (dstExists)
*dstExists = false;
if (link(source, destination) == 0) {
return true;
} else {
if (errno == EEXIST) {
// Should kick-in before MAC, so avoid the hassle
if (dstExists)
*dstExists = true;
return false;
} else {
PLOG_D("Couldn't link '%s' as '%s'", source, destination);
/*
* Don't fail yet as we might have a running env which doesn't allow
* hardlinks (e.g. SELinux)
*/
}
}
// Now try with a verbose POSIX alternative
int inFD, outFD, dstOpenFlags;
mode_t dstFilePerms;
// O_EXCL is important for saving unique crashes
dstOpenFlags = O_CREAT | O_WRONLY | O_EXCL;
dstFilePerms = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
inFD = open(source, O_RDONLY);
if (inFD == -1) {
PLOG_D("Couldn't open '%s' source", source);
return false;
}
defer {
close(inFD);
};
struct stat inSt;
if (fstat(inFD, &inSt) == -1) {
PLOG_W("Couldn't fstat(fd='%d' fileName='%s')", inFD, source);
return false;
}
outFD = open(destination, dstOpenFlags, dstFilePerms);
if (outFD == -1) {
if (errno == EEXIST) {
if (dstExists)
*dstExists = true;
}
PLOG_D("Couldn't open '%s' destination", destination);
return false;
}
defer {
close(outFD);
};
uint8_t *inFileBuf = malloc(inSt.st_size);
if (!inFileBuf) {
PLOG_W("malloc(%zu) failed", (size_t) inSt.st_size);
return false;
}
defer {
free(inFileBuf);
};
ssize_t readSz = files_readFromFd(inFD, inFileBuf, (size_t) inSt.st_size);
if (readSz < 0) {
PLOG_W("Couldn't read '%s' to a buf", source);
return false;
}
if (files_writeToFd(outFD, inFileBuf, readSz) == false) {
PLOG_W("Couldn't write '%zu' bytes to file '%s' (fd='%d')", (size_t) readSz,
destination, outFD);
unlink(destination);
return false;
}
return true;
}