#include "btrfs.h"
#include "common/io/io.h"
#include <fcntl.h>
enum { uuidLen = (uint32_t) __builtin_strlen("00000000-0000-0000-0000-000000000000") };
static const char* enumerateDevices(FFBtrfsResult* item, int dfd, FFstrbuf* buffer)
{
int subfd = openat(dfd, "devices", O_RDONLY | O_CLOEXEC | O_DIRECTORY);
if (subfd < 0) return "openat(\"/sys/fs/btrfs/UUID/devices\") == -1";
FF_AUTO_CLOSE_DIR DIR* dirp = fdopendir(subfd);
if(dirp == NULL)
{
close(subfd);
return "fdopendir(\"/sys/fs/btrfs/UUID/devices\") == NULL";
}
struct dirent* entry;
while ((entry = readdir(dirp)) != NULL)
{
if (entry->d_name[0] == '.')
continue;
if (item->devices.length)
ffStrbufAppendC(&item->devices, ',');
ffStrbufAppendS(&item->devices, entry->d_name);
char path[sizeof(entry->d_name) + sizeof("/size") + 1];
snprintf(path, ARRAY_SIZE(path), "%s/size", entry->d_name);
if (ffReadFileBufferRelative(subfd, path, buffer))
item->totalSize += ffStrbufToUInt(buffer, 0) * 512;
}
return NULL;
}
static const char* enumerateFeatures(FFBtrfsResult* item, int dfd)
{
int subfd = openat(dfd, "features", O_RDONLY | O_CLOEXEC | O_DIRECTORY);
if (subfd < 0) return "openat(\"/sys/fs/btrfs/UUID/features\") == -1";
FF_AUTO_CLOSE_DIR DIR* dirp = fdopendir(subfd);
if(dirp == NULL)
return "fdopendir(\"/sys/fs/btrfs/UUID/features\") == NULL";
struct dirent* entry;
while ((entry = readdir(dirp)) != NULL)
{
if (entry->d_name[0] == '.')
continue;
if (item->features.length)
ffStrbufAppendC(&item->features, ',');
ffStrbufAppendS(&item->features, entry->d_name);
}
return NULL;
}
static const char* detectAllocation(FFBtrfsResult* item, int dfd, FFstrbuf* buffer)
{
FF_AUTO_CLOSE_FD int subfd = openat(dfd, "allocation", O_RDONLY | O_CLOEXEC | O_PATH | O_DIRECTORY);
if (subfd < 0) return "openat(\"/sys/fs/btrfs/UUID/allocation\") == -1";
if (ffReadFileBufferRelative(subfd, "global_rsv_size", buffer))
item->globalReservationTotal = ffStrbufToUInt(buffer, 0);
else
return "ffReadFileBuffer(\"/sys/fs/btrfs/UUID/allocation/global_rsv_size\") == NULL";
if (ffReadFileBufferRelative(subfd, "global_rsv_reserved", buffer))
item->globalReservationUsed = ffStrbufToUInt(buffer, 0);
item->globalReservationUsed = item->globalReservationTotal - item->globalReservationUsed;
#define FF_BTRFS_DETECT_TYPE(index, _type) \
if (ffReadFileBufferRelative(subfd, #_type "/total_bytes", buffer)) \
item->allocation[index].total = ffStrbufToUInt(buffer, 0); \
\
if (ffReadFileBufferRelative(subfd, #_type "/bytes_used", buffer)) \
item->allocation[index].used = ffStrbufToUInt(buffer, 0); \
\
item->allocation[index].dup = faccessat(subfd, #_type "/dup/", F_OK, 0) == 0; \
\
item->allocation[index].type = #_type;
FF_BTRFS_DETECT_TYPE(0, data);
FF_BTRFS_DETECT_TYPE(1, metadata);
FF_BTRFS_DETECT_TYPE(2, system);
#undef FF_BTRFS_DETECT_TYPE
return NULL;
}
const char* ffDetectBtrfs(FFlist* result)
{
FF_AUTO_CLOSE_DIR DIR* dirp = opendir("/sys/fs/btrfs/");
if(dirp == NULL)
return "opendir(\"/sys/fs/btrfs\") == NULL";
FF_STRBUF_AUTO_DESTROY buffer = ffStrbufCreate();
struct dirent* entry;
while ((entry = readdir(dirp)) != NULL)
{
if (entry->d_name[0] == '.')
continue;
if (strlen(entry->d_name) != uuidLen)
continue;
FFBtrfsResult* item = ffListAdd(result);
(*item) = (FFBtrfsResult){
.uuid = ffStrbufCreateNS(uuidLen, entry->d_name),
.name = ffStrbufCreate(),
.devices = ffStrbufCreate(),
.features = ffStrbufCreate(),
};
FF_AUTO_CLOSE_FD int dfd = openat(dirfd(dirp), entry->d_name, O_RDONLY | O_CLOEXEC | O_PATH | O_DIRECTORY);
if (dfd < 0) continue;
if (ffAppendFileBufferRelative(dfd, "label", &item->name))
ffStrbufTrimRightSpace(&item->name);
enumerateDevices(item, dfd, &buffer);
enumerateFeatures(item, dfd);
if (ffReadFileBufferRelative(dfd, "generation", &buffer))
item->generation = (uint32_t) ffStrbufToUInt(&buffer, 0);
if (ffReadFileBufferRelative(dfd, "nodesize", &buffer))
item->nodeSize = (uint32_t) ffStrbufToUInt(&buffer, 0);
if (ffReadFileBufferRelative(dfd, "sectorsize", &buffer))
item->sectorSize = (uint32_t) ffStrbufToUInt(&buffer, 0);
detectAllocation(item, dfd, &buffer);
}
return NULL;
}