diff options
Diffstat (limited to 'statinfo.h')
-rw-r--r-- | statinfo.h | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/statinfo.h b/statinfo.h new file mode 100644 index 0000000..700f502 --- /dev/null +++ b/statinfo.h @@ -0,0 +1,89 @@ +#ifndef STATINFO_H +#define STATINFO_H + +struct index_state; + +/* + * The "cache_time" is just the low 32 bits of the + * time. It doesn't matter if it overflows - we only + * check it for equality in the 32 bits we save. + */ +struct cache_time { + uint32_t sec; + uint32_t nsec; +}; + +struct stat_data { + struct cache_time sd_ctime; + struct cache_time sd_mtime; + unsigned int sd_dev; + unsigned int sd_ino; + unsigned int sd_uid; + unsigned int sd_gid; + unsigned int sd_size; +}; + +/* + * A struct to encapsulate the concept of whether a file has changed + * since we last checked it. This uses criteria similar to those used + * for the index. + */ +struct stat_validity { + struct stat_data *sd; +}; + +#define MTIME_CHANGED 0x0001 +#define CTIME_CHANGED 0x0002 +#define OWNER_CHANGED 0x0004 +#define MODE_CHANGED 0x0008 +#define INODE_CHANGED 0x0010 +#define DATA_CHANGED 0x0020 +#define TYPE_CHANGED 0x0040 + +/* + * Record to sd the data from st that we use to check whether a file + * might have changed. + */ +void fill_stat_data(struct stat_data *sd, struct stat *st); + +/* + * Return 0 if st is consistent with a file not having been changed + * since sd was filled. If there are differences, return a + * combination of MTIME_CHANGED, CTIME_CHANGED, OWNER_CHANGED, + * INODE_CHANGED, and DATA_CHANGED. + */ +int match_stat_data(const struct stat_data *sd, struct stat *st); + +void stat_validity_clear(struct stat_validity *sv); + +/* + * Returns 1 if the path is a regular file (or a symlink to a regular + * file) and matches the saved stat_validity, 0 otherwise. A missing + * or inaccessible file is considered a match if the struct was just + * initialized, or if the previous update found an inaccessible file. + */ +int stat_validity_check(struct stat_validity *sv, const char *path); + +/* + * Update the stat_validity from a file opened at descriptor fd. If + * the file is missing, inaccessible, or not a regular file, then + * future calls to stat_validity_check will match iff one of those + * conditions continues to be true. + */ +void stat_validity_update(struct stat_validity *sv, int fd); + +#if defined(DT_UNKNOWN) && !defined(NO_D_TYPE_IN_DIRENT) +#define DTYPE(de) ((de)->d_type) +#else +#undef DT_UNKNOWN +#undef DT_DIR +#undef DT_REG +#undef DT_LNK +#define DT_UNKNOWN 0 +#define DT_DIR 1 +#define DT_REG 2 +#define DT_LNK 3 +#define DTYPE(de) DT_UNKNOWN +#endif + +#endif |