From 1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5 Mon Sep 17 00:00:00 2001 From: Vincent Ambo Date: Sat, 11 Jan 2020 23:36:56 +0000 Subject: Squashed 'third_party/git/' content from commit cb71568594 git-subtree-dir: third_party/git git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7 --- fsmonitor.c | 262 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 262 insertions(+) create mode 100644 fsmonitor.c (limited to 'fsmonitor.c') diff --git a/fsmonitor.c b/fsmonitor.c new file mode 100644 index 000000000000..231e83a94db5 --- /dev/null +++ b/fsmonitor.c @@ -0,0 +1,262 @@ +#include "cache.h" +#include "config.h" +#include "dir.h" +#include "ewah/ewok.h" +#include "fsmonitor.h" +#include "run-command.h" +#include "strbuf.h" + +#define INDEX_EXTENSION_VERSION (1) +#define HOOK_INTERFACE_VERSION (1) + +struct trace_key trace_fsmonitor = TRACE_KEY_INIT(FSMONITOR); + +static void fsmonitor_ewah_callback(size_t pos, void *is) +{ + struct index_state *istate = (struct index_state *)is; + struct cache_entry *ce = istate->cache[pos]; + + ce->ce_flags &= ~CE_FSMONITOR_VALID; +} + +int read_fsmonitor_extension(struct index_state *istate, const void *data, + unsigned long sz) +{ + const char *index = data; + uint32_t hdr_version; + uint32_t ewah_size; + struct ewah_bitmap *fsmonitor_dirty; + int ret; + + if (sz < sizeof(uint32_t) + sizeof(uint64_t) + sizeof(uint32_t)) + return error("corrupt fsmonitor extension (too short)"); + + hdr_version = get_be32(index); + index += sizeof(uint32_t); + if (hdr_version != INDEX_EXTENSION_VERSION) + return error("bad fsmonitor version %d", hdr_version); + + istate->fsmonitor_last_update = get_be64(index); + index += sizeof(uint64_t); + + ewah_size = get_be32(index); + index += sizeof(uint32_t); + + fsmonitor_dirty = ewah_new(); + ret = ewah_read_mmap(fsmonitor_dirty, index, ewah_size); + if (ret != ewah_size) { + ewah_free(fsmonitor_dirty); + return error("failed to parse ewah bitmap reading fsmonitor index extension"); + } + istate->fsmonitor_dirty = fsmonitor_dirty; + + trace_printf_key(&trace_fsmonitor, "read fsmonitor extension successful"); + return 0; +} + +void fill_fsmonitor_bitmap(struct index_state *istate) +{ + unsigned int i; + istate->fsmonitor_dirty = ewah_new(); + for (i = 0; i < istate->cache_nr; i++) + if (!(istate->cache[i]->ce_flags & CE_FSMONITOR_VALID)) + ewah_set(istate->fsmonitor_dirty, i); +} + +void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate) +{ + uint32_t hdr_version; + uint64_t tm; + uint32_t ewah_start; + uint32_t ewah_size = 0; + int fixup = 0; + + put_be32(&hdr_version, INDEX_EXTENSION_VERSION); + strbuf_add(sb, &hdr_version, sizeof(uint32_t)); + + put_be64(&tm, istate->fsmonitor_last_update); + strbuf_add(sb, &tm, sizeof(uint64_t)); + fixup = sb->len; + strbuf_add(sb, &ewah_size, sizeof(uint32_t)); /* we'll fix this up later */ + + ewah_start = sb->len; + ewah_serialize_strbuf(istate->fsmonitor_dirty, sb); + ewah_free(istate->fsmonitor_dirty); + istate->fsmonitor_dirty = NULL; + + /* fix up size field */ + put_be32(&ewah_size, sb->len - ewah_start); + memcpy(sb->buf + fixup, &ewah_size, sizeof(uint32_t)); + + trace_printf_key(&trace_fsmonitor, "write fsmonitor extension successful"); +} + +/* + * Call the query-fsmonitor hook passing the time of the last saved results. + */ +static int query_fsmonitor(int version, uint64_t last_update, struct strbuf *query_result) +{ + struct child_process cp = CHILD_PROCESS_INIT; + + if (!core_fsmonitor) + return -1; + + argv_array_push(&cp.args, core_fsmonitor); + argv_array_pushf(&cp.args, "%d", version); + argv_array_pushf(&cp.args, "%" PRIuMAX, (uintmax_t)last_update); + cp.use_shell = 1; + cp.dir = get_git_work_tree(); + + return capture_command(&cp, query_result, 1024); +} + +static void fsmonitor_refresh_callback(struct index_state *istate, const char *name) +{ + int pos = index_name_pos(istate, name, strlen(name)); + + if (pos >= 0) { + struct cache_entry *ce = istate->cache[pos]; + ce->ce_flags &= ~CE_FSMONITOR_VALID; + } + + /* + * Mark the untracked cache dirty even if it wasn't found in the index + * as it could be a new untracked file. + */ + trace_printf_key(&trace_fsmonitor, "fsmonitor_refresh_callback '%s'", name); + untracked_cache_invalidate_path(istate, name, 0); +} + +void refresh_fsmonitor(struct index_state *istate) +{ + struct strbuf query_result = STRBUF_INIT; + int query_success = 0; + size_t bol; /* beginning of line */ + uint64_t last_update; + char *buf; + unsigned int i; + + if (!core_fsmonitor || istate->fsmonitor_has_run_once) + return; + istate->fsmonitor_has_run_once = 1; + + trace_printf_key(&trace_fsmonitor, "refresh fsmonitor"); + /* + * This could be racy so save the date/time now and query_fsmonitor + * should be inclusive to ensure we don't miss potential changes. + */ + last_update = getnanotime(); + + /* + * If we have a last update time, call query_fsmonitor for the set of + * changes since that time, else assume everything is possibly dirty + * and check it all. + */ + if (istate->fsmonitor_last_update) { + query_success = !query_fsmonitor(HOOK_INTERFACE_VERSION, + istate->fsmonitor_last_update, &query_result); + trace_performance_since(last_update, "fsmonitor process '%s'", core_fsmonitor); + trace_printf_key(&trace_fsmonitor, "fsmonitor process '%s' returned %s", + core_fsmonitor, query_success ? "success" : "failure"); + } + + /* a fsmonitor process can return '/' to indicate all entries are invalid */ + if (query_success && query_result.buf[0] != '/') { + /* Mark all entries returned by the monitor as dirty */ + buf = query_result.buf; + bol = 0; + for (i = 0; i < query_result.len; i++) { + if (buf[i] != '\0') + continue; + fsmonitor_refresh_callback(istate, buf + bol); + bol = i + 1; + } + if (bol < query_result.len) + fsmonitor_refresh_callback(istate, buf + bol); + } else { + /* Mark all entries invalid */ + for (i = 0; i < istate->cache_nr; i++) + istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID; + + /* If we're going to check every file, ensure we save the results */ + istate->cache_changed |= FSMONITOR_CHANGED; + + if (istate->untracked) + istate->untracked->use_fsmonitor = 0; + } + strbuf_release(&query_result); + + /* Now that we've updated istate, save the last_update time */ + istate->fsmonitor_last_update = last_update; +} + +void add_fsmonitor(struct index_state *istate) +{ + unsigned int i; + + if (!istate->fsmonitor_last_update) { + trace_printf_key(&trace_fsmonitor, "add fsmonitor"); + istate->cache_changed |= FSMONITOR_CHANGED; + istate->fsmonitor_last_update = getnanotime(); + + /* reset the fsmonitor state */ + for (i = 0; i < istate->cache_nr; i++) + istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID; + + /* reset the untracked cache */ + if (istate->untracked) { + add_untracked_cache(istate); + istate->untracked->use_fsmonitor = 1; + } + + /* Update the fsmonitor state */ + refresh_fsmonitor(istate); + } +} + +void remove_fsmonitor(struct index_state *istate) +{ + if (istate->fsmonitor_last_update) { + trace_printf_key(&trace_fsmonitor, "remove fsmonitor"); + istate->cache_changed |= FSMONITOR_CHANGED; + istate->fsmonitor_last_update = 0; + } +} + +void tweak_fsmonitor(struct index_state *istate) +{ + unsigned int i; + int fsmonitor_enabled = git_config_get_fsmonitor(); + + if (istate->fsmonitor_dirty) { + if (fsmonitor_enabled) { + /* Mark all entries valid */ + for (i = 0; i < istate->cache_nr; i++) { + istate->cache[i]->ce_flags |= CE_FSMONITOR_VALID; + } + + /* Mark all previously saved entries as dirty */ + ewah_each_bit(istate->fsmonitor_dirty, fsmonitor_ewah_callback, istate); + + /* Now mark the untracked cache for fsmonitor usage */ + if (istate->untracked) + istate->untracked->use_fsmonitor = 1; + } + + ewah_free(istate->fsmonitor_dirty); + istate->fsmonitor_dirty = NULL; + } + + switch (fsmonitor_enabled) { + case -1: /* keep: do nothing */ + break; + case 0: /* false */ + remove_fsmonitor(istate); + break; + case 1: /* true */ + add_fsmonitor(istate); + break; + default: /* unknown value: do nothing */ + break; + } +} -- cgit 1.4.1