From 38612532240ecbe1b12e54ca859fed8410ae6de1 Mon Sep 17 00:00:00 2001 From: Michael Haggerty Date: Thu, 20 Jun 2013 10:37:51 +0200 Subject: add a stat_validity struct It can sometimes be useful to know whether a path in the filesystem has been updated without going to the work of opening and re-reading its content. We trust the stat() information on disk already to handle index updates, and we can use the same trick here. This patch introduces a "stat_validity" struct which encapsulates the concept of checking the stat-freshness of a file. It is implemented on top of "struct stat_data" to reuse the logic about which stat entries to trust for a particular platform, but hides the complexity behind two simple functions: check and update. Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano --- read-cache.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'read-cache.c') diff --git a/read-cache.c b/read-cache.c index 5660b37bb2..b15bc096ea 100644 --- a/read-cache.c +++ b/read-cache.c @@ -1950,3 +1950,33 @@ void *read_blob_data_from_index(struct index_state *istate, const char *path, un *size = sz; return data; } + +void stat_validity_clear(struct stat_validity *sv) +{ + free(sv->sd); + sv->sd = NULL; +} + +int stat_validity_check(struct stat_validity *sv, const char *path) +{ + struct stat st; + + if (stat(path, &st) < 0) + return sv->sd == NULL; + if (!sv->sd) + return 0; + return S_ISREG(st.st_mode) && !match_stat_data(sv->sd, &st); +} + +void stat_validity_update(struct stat_validity *sv, int fd) +{ + struct stat st; + + if (fstat(fd, &st) < 0 || !S_ISREG(st.st_mode)) + stat_validity_clear(sv); + else { + if (!sv->sd) + sv->sd = xcalloc(1, sizeof(struct stat_data)); + fill_stat_data(sv->sd, &st); + } +} -- cgit v1.2.1