git

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#include "git-compat-util.h"
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#include "environment.h"
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#include "statinfo.h"
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/*
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 * Munge st_size into an unsigned int.
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 */
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static unsigned int munge_st_size(off_t st_size) {
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	unsigned int sd_size = st_size;
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	/*
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	 * If the file is an exact multiple of 4 GiB, modify the value so it
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	 * doesn't get marked as racily clean (zero).
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	 */
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	if (!sd_size && st_size)
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		return 0x80000000;
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	else
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		return sd_size;
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}
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void fill_stat_data(struct stat_data *sd, struct stat *st)
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{
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	sd->sd_ctime.sec = (unsigned int)st->st_ctime;
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	sd->sd_mtime.sec = (unsigned int)st->st_mtime;
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	sd->sd_ctime.nsec = ST_CTIME_NSEC(*st);
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	sd->sd_mtime.nsec = ST_MTIME_NSEC(*st);
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	sd->sd_dev = st->st_dev;
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	sd->sd_ino = st->st_ino;
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	sd->sd_uid = st->st_uid;
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	sd->sd_gid = st->st_gid;
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	sd->sd_size = munge_st_size(st->st_size);
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}
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static void set_times(struct stat *st, const struct stat_data *sd)
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{
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	st->st_ctime = sd->sd_ctime.sec;
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	st->st_mtime = sd->sd_mtime.sec;
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#ifdef NO_NSEC
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	; /* nothing */
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#else
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#ifdef USE_ST_TIMESPEC
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	st->st_ctimespec.tv_nsec = sd->sd_ctime.nsec;
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	st->st_mtimespec.tv_nsec = sd->sd_mtime.nsec;
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#else
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	st->st_ctim.tv_nsec = sd->sd_ctime.nsec;
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	st->st_mtim.tv_nsec = sd->sd_mtime.nsec;
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#endif
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#endif
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}
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void fake_lstat_data(const struct stat_data *sd, struct stat *st)
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{
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	set_times(st, sd);
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	st->st_dev = sd->sd_dev;
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	st->st_ino = sd->sd_ino;
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	st->st_uid = sd->sd_uid;
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	st->st_gid = sd->sd_gid;
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	st->st_size = sd->sd_size;
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}
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int match_stat_data(const struct stat_data *sd, struct stat *st)
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{
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	int changed = 0;
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	if (sd->sd_mtime.sec != (unsigned int)st->st_mtime)
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		changed |= MTIME_CHANGED;
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	if (trust_ctime && check_stat &&
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	    sd->sd_ctime.sec != (unsigned int)st->st_ctime)
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		changed |= CTIME_CHANGED;
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#ifdef USE_NSEC
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	if (check_stat && sd->sd_mtime.nsec != ST_MTIME_NSEC(*st))
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		changed |= MTIME_CHANGED;
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	if (trust_ctime && check_stat &&
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	    sd->sd_ctime.nsec != ST_CTIME_NSEC(*st))
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		changed |= CTIME_CHANGED;
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#endif
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	if (check_stat) {
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		if (sd->sd_uid != (unsigned int) st->st_uid ||
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			sd->sd_gid != (unsigned int) st->st_gid)
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			changed |= OWNER_CHANGED;
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		if (sd->sd_ino != (unsigned int) st->st_ino)
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			changed |= INODE_CHANGED;
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	}
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#ifdef USE_STDEV
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	/*
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	 * st_dev breaks on network filesystems where different
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	 * clients will have different views of what "device"
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	 * the filesystem is on
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	 */
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	if (check_stat && sd->sd_dev != (unsigned int) st->st_dev)
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			changed |= INODE_CHANGED;
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#endif
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	if (sd->sd_size != munge_st_size(st->st_size))
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		changed |= DATA_CHANGED;
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	return changed;
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}
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void stat_validity_clear(struct stat_validity *sv)
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{
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	FREE_AND_NULL(sv->sd);
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}
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int stat_validity_check(struct stat_validity *sv, const char *path)
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{
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	struct stat st;
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	if (stat(path, &st) < 0)
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		return sv->sd == NULL;
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	if (!sv->sd)
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		return 0;
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	return S_ISREG(st.st_mode) && !match_stat_data(sv->sd, &st);
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}
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void stat_validity_update(struct stat_validity *sv, int fd)
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{
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	struct stat st;
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	if (fstat(fd, &st) < 0 || !S_ISREG(st.st_mode))
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		stat_validity_clear(sv);
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	else {
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		if (!sv->sd)
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			CALLOC_ARRAY(sv->sd, 1);
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		fill_stat_data(sv->sd, &st);
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	}
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}
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