Fourth batch
[git.git] / fsmonitor.c
blobed796e3e03a4c7132e7329d729b57cdae3cf9da6
1 #include "cache.h"
2 #include "config.h"
3 #include "dir.h"
4 #include "ewah/ewok.h"
5 #include "fsmonitor.h"
6 #include "run-command.h"
7 #include "strbuf.h"
9 #define INDEX_EXTENSION_VERSION1 (1)
10 #define INDEX_EXTENSION_VERSION2 (2)
11 #define HOOK_INTERFACE_VERSION1 (1)
12 #define HOOK_INTERFACE_VERSION2 (2)
14 struct trace_key trace_fsmonitor = TRACE_KEY_INIT(FSMONITOR);
16 static void fsmonitor_ewah_callback(size_t pos, void *is)
18 struct index_state *istate = (struct index_state *)is;
19 struct cache_entry *ce;
21 if (pos >= istate->cache_nr)
22 BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" >= %u)",
23 (uintmax_t)pos, istate->cache_nr);
25 ce = istate->cache[pos];
26 ce->ce_flags &= ~CE_FSMONITOR_VALID;
29 static int fsmonitor_hook_version(void)
31 int hook_version;
33 if (git_config_get_int("core.fsmonitorhookversion", &hook_version))
34 return -1;
36 if (hook_version == HOOK_INTERFACE_VERSION1 ||
37 hook_version == HOOK_INTERFACE_VERSION2)
38 return hook_version;
40 warning("Invalid hook version '%i' in core.fsmonitorhookversion. "
41 "Must be 1 or 2.", hook_version);
42 return -1;
45 int read_fsmonitor_extension(struct index_state *istate, const void *data,
46 unsigned long sz)
48 const char *index = data;
49 uint32_t hdr_version;
50 uint32_t ewah_size;
51 struct ewah_bitmap *fsmonitor_dirty;
52 int ret;
53 uint64_t timestamp;
54 struct strbuf last_update = STRBUF_INIT;
56 if (sz < sizeof(uint32_t) + 1 + sizeof(uint32_t))
57 return error("corrupt fsmonitor extension (too short)");
59 hdr_version = get_be32(index);
60 index += sizeof(uint32_t);
61 if (hdr_version == INDEX_EXTENSION_VERSION1) {
62 timestamp = get_be64(index);
63 strbuf_addf(&last_update, "%"PRIu64"", timestamp);
64 index += sizeof(uint64_t);
65 } else if (hdr_version == INDEX_EXTENSION_VERSION2) {
66 strbuf_addstr(&last_update, index);
67 index += last_update.len + 1;
68 } else {
69 return error("bad fsmonitor version %d", hdr_version);
72 istate->fsmonitor_last_update = strbuf_detach(&last_update, NULL);
74 ewah_size = get_be32(index);
75 index += sizeof(uint32_t);
77 fsmonitor_dirty = ewah_new();
78 ret = ewah_read_mmap(fsmonitor_dirty, index, ewah_size);
79 if (ret != ewah_size) {
80 ewah_free(fsmonitor_dirty);
81 return error("failed to parse ewah bitmap reading fsmonitor index extension");
83 istate->fsmonitor_dirty = fsmonitor_dirty;
85 if (!istate->split_index &&
86 istate->fsmonitor_dirty->bit_size > istate->cache_nr)
87 BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)",
88 (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr);
90 trace_printf_key(&trace_fsmonitor, "read fsmonitor extension successful");
91 return 0;
94 void fill_fsmonitor_bitmap(struct index_state *istate)
96 unsigned int i, skipped = 0;
97 istate->fsmonitor_dirty = ewah_new();
98 for (i = 0; i < istate->cache_nr; i++) {
99 if (istate->cache[i]->ce_flags & CE_REMOVE)
100 skipped++;
101 else if (!(istate->cache[i]->ce_flags & CE_FSMONITOR_VALID))
102 ewah_set(istate->fsmonitor_dirty, i - skipped);
106 void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate)
108 uint32_t hdr_version;
109 uint32_t ewah_start;
110 uint32_t ewah_size = 0;
111 int fixup = 0;
113 if (!istate->split_index &&
114 istate->fsmonitor_dirty->bit_size > istate->cache_nr)
115 BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)",
116 (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr);
118 put_be32(&hdr_version, INDEX_EXTENSION_VERSION2);
119 strbuf_add(sb, &hdr_version, sizeof(uint32_t));
121 strbuf_addstr(sb, istate->fsmonitor_last_update);
122 strbuf_addch(sb, 0); /* Want to keep a NUL */
124 fixup = sb->len;
125 strbuf_add(sb, &ewah_size, sizeof(uint32_t)); /* we'll fix this up later */
127 ewah_start = sb->len;
128 ewah_serialize_strbuf(istate->fsmonitor_dirty, sb);
129 ewah_free(istate->fsmonitor_dirty);
130 istate->fsmonitor_dirty = NULL;
132 /* fix up size field */
133 put_be32(&ewah_size, sb->len - ewah_start);
134 memcpy(sb->buf + fixup, &ewah_size, sizeof(uint32_t));
136 trace_printf_key(&trace_fsmonitor, "write fsmonitor extension successful");
140 * Call the query-fsmonitor hook passing the last update token of the saved results.
142 static int query_fsmonitor(int version, const char *last_update, struct strbuf *query_result)
144 struct child_process cp = CHILD_PROCESS_INIT;
146 if (!core_fsmonitor)
147 return -1;
149 argv_array_push(&cp.args, core_fsmonitor);
150 argv_array_pushf(&cp.args, "%d", version);
151 argv_array_pushf(&cp.args, "%s", last_update);
152 cp.use_shell = 1;
153 cp.dir = get_git_work_tree();
155 return capture_command(&cp, query_result, 1024);
158 static void fsmonitor_refresh_callback(struct index_state *istate, const char *name)
160 int pos = index_name_pos(istate, name, strlen(name));
162 if (pos >= 0) {
163 struct cache_entry *ce = istate->cache[pos];
164 ce->ce_flags &= ~CE_FSMONITOR_VALID;
168 * Mark the untracked cache dirty even if it wasn't found in the index
169 * as it could be a new untracked file.
171 trace_printf_key(&trace_fsmonitor, "fsmonitor_refresh_callback '%s'", name);
172 untracked_cache_invalidate_path(istate, name, 0);
175 void refresh_fsmonitor(struct index_state *istate)
177 struct strbuf query_result = STRBUF_INIT;
178 int query_success = 0, hook_version = -1;
179 size_t bol = 0; /* beginning of line */
180 uint64_t last_update;
181 struct strbuf last_update_token = STRBUF_INIT;
182 char *buf;
183 unsigned int i;
185 if (!core_fsmonitor || istate->fsmonitor_has_run_once)
186 return;
188 hook_version = fsmonitor_hook_version();
190 istate->fsmonitor_has_run_once = 1;
192 trace_printf_key(&trace_fsmonitor, "refresh fsmonitor");
194 * This could be racy so save the date/time now and query_fsmonitor
195 * should be inclusive to ensure we don't miss potential changes.
197 last_update = getnanotime();
198 if (hook_version == HOOK_INTERFACE_VERSION1)
199 strbuf_addf(&last_update_token, "%"PRIu64"", last_update);
202 * If we have a last update token, call query_fsmonitor for the set of
203 * changes since that token, else assume everything is possibly dirty
204 * and check it all.
206 if (istate->fsmonitor_last_update) {
207 if (hook_version == -1 || hook_version == HOOK_INTERFACE_VERSION2) {
208 query_success = !query_fsmonitor(HOOK_INTERFACE_VERSION2,
209 istate->fsmonitor_last_update, &query_result);
211 if (query_success) {
212 if (hook_version < 0)
213 hook_version = HOOK_INTERFACE_VERSION2;
216 * First entry will be the last update token
217 * Need to use a char * variable because static
218 * analysis was suggesting to use strbuf_addbuf
219 * but we don't want to copy the entire strbuf
220 * only the chars up to the first NUL
222 buf = query_result.buf;
223 strbuf_addstr(&last_update_token, buf);
224 if (!last_update_token.len) {
225 warning("Empty last update token.");
226 query_success = 0;
227 } else {
228 bol = last_update_token.len + 1;
230 } else if (hook_version < 0) {
231 hook_version = HOOK_INTERFACE_VERSION1;
232 if (!last_update_token.len)
233 strbuf_addf(&last_update_token, "%"PRIu64"", last_update);
237 if (hook_version == HOOK_INTERFACE_VERSION1) {
238 query_success = !query_fsmonitor(HOOK_INTERFACE_VERSION1,
239 istate->fsmonitor_last_update, &query_result);
242 trace_performance_since(last_update, "fsmonitor process '%s'", core_fsmonitor);
243 trace_printf_key(&trace_fsmonitor, "fsmonitor process '%s' returned %s",
244 core_fsmonitor, query_success ? "success" : "failure");
247 /* a fsmonitor process can return '/' to indicate all entries are invalid */
248 if (query_success && query_result.buf[bol] != '/') {
249 /* Mark all entries returned by the monitor as dirty */
250 buf = query_result.buf;
251 for (i = bol; i < query_result.len; i++) {
252 if (buf[i] != '\0')
253 continue;
254 fsmonitor_refresh_callback(istate, buf + bol);
255 bol = i + 1;
257 if (bol < query_result.len)
258 fsmonitor_refresh_callback(istate, buf + bol);
260 /* Now mark the untracked cache for fsmonitor usage */
261 if (istate->untracked)
262 istate->untracked->use_fsmonitor = 1;
263 } else {
265 /* We only want to run the post index changed hook if we've actually changed entries, so keep track
266 * if we actually changed entries or not */
267 int is_cache_changed = 0;
268 /* Mark all entries invalid */
269 for (i = 0; i < istate->cache_nr; i++) {
270 if (istate->cache[i]->ce_flags & CE_FSMONITOR_VALID) {
271 is_cache_changed = 1;
272 istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
276 /* If we're going to check every file, ensure we save the results */
277 if (is_cache_changed)
278 istate->cache_changed |= FSMONITOR_CHANGED;
280 if (istate->untracked)
281 istate->untracked->use_fsmonitor = 0;
283 strbuf_release(&query_result);
285 /* Now that we've updated istate, save the last_update_token */
286 FREE_AND_NULL(istate->fsmonitor_last_update);
287 istate->fsmonitor_last_update = strbuf_detach(&last_update_token, NULL);
290 void add_fsmonitor(struct index_state *istate)
292 unsigned int i;
293 struct strbuf last_update = STRBUF_INIT;
295 if (!istate->fsmonitor_last_update) {
296 trace_printf_key(&trace_fsmonitor, "add fsmonitor");
297 istate->cache_changed |= FSMONITOR_CHANGED;
298 strbuf_addf(&last_update, "%"PRIu64"", getnanotime());
299 istate->fsmonitor_last_update = strbuf_detach(&last_update, NULL);
301 /* reset the fsmonitor state */
302 for (i = 0; i < istate->cache_nr; i++)
303 istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
305 /* reset the untracked cache */
306 if (istate->untracked) {
307 add_untracked_cache(istate);
308 istate->untracked->use_fsmonitor = 1;
311 /* Update the fsmonitor state */
312 refresh_fsmonitor(istate);
316 void remove_fsmonitor(struct index_state *istate)
318 if (istate->fsmonitor_last_update) {
319 trace_printf_key(&trace_fsmonitor, "remove fsmonitor");
320 istate->cache_changed |= FSMONITOR_CHANGED;
321 FREE_AND_NULL(istate->fsmonitor_last_update);
325 void tweak_fsmonitor(struct index_state *istate)
327 unsigned int i;
328 int fsmonitor_enabled = git_config_get_fsmonitor();
330 if (istate->fsmonitor_dirty) {
331 if (fsmonitor_enabled) {
332 /* Mark all entries valid */
333 for (i = 0; i < istate->cache_nr; i++) {
334 istate->cache[i]->ce_flags |= CE_FSMONITOR_VALID;
337 /* Mark all previously saved entries as dirty */
338 if (istate->fsmonitor_dirty->bit_size > istate->cache_nr)
339 BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)",
340 (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr);
341 ewah_each_bit(istate->fsmonitor_dirty, fsmonitor_ewah_callback, istate);
343 refresh_fsmonitor(istate);
346 ewah_free(istate->fsmonitor_dirty);
347 istate->fsmonitor_dirty = NULL;
350 switch (fsmonitor_enabled) {
351 case -1: /* keep: do nothing */
352 break;
353 case 0: /* false */
354 remove_fsmonitor(istate);
355 break;
356 case 1: /* true */
357 add_fsmonitor(istate);
358 break;
359 default: /* unknown value: do nothing */
360 break;