6 #include "run-command.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)
33 if (git_config_get_int("core.fsmonitorhookversion", &hook_version
))
36 if (hook_version
== HOOK_INTERFACE_VERSION1
||
37 hook_version
== HOOK_INTERFACE_VERSION2
)
40 warning("Invalid hook version '%i' in core.fsmonitorhookversion. "
41 "Must be 1 or 2.", hook_version
);
45 int read_fsmonitor_extension(struct index_state
*istate
, const void *data
,
48 const char *index
= data
;
51 struct ewah_bitmap
*fsmonitor_dirty
;
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;
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 trace2_data_string("index", NULL
, "extension/fsmn/read/token",
91 istate
->fsmonitor_last_update
);
92 trace_printf_key(&trace_fsmonitor
,
93 "read fsmonitor extension successful '%s'",
94 istate
->fsmonitor_last_update
);
98 void fill_fsmonitor_bitmap(struct index_state
*istate
)
100 unsigned int i
, skipped
= 0;
101 istate
->fsmonitor_dirty
= ewah_new();
102 for (i
= 0; i
< istate
->cache_nr
; i
++) {
103 if (istate
->cache
[i
]->ce_flags
& CE_REMOVE
)
105 else if (!(istate
->cache
[i
]->ce_flags
& CE_FSMONITOR_VALID
))
106 ewah_set(istate
->fsmonitor_dirty
, i
- skipped
);
110 void write_fsmonitor_extension(struct strbuf
*sb
, struct index_state
*istate
)
112 uint32_t hdr_version
;
114 uint32_t ewah_size
= 0;
117 if (!istate
->split_index
&&
118 istate
->fsmonitor_dirty
->bit_size
> istate
->cache_nr
)
119 BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX
" > %u)",
120 (uintmax_t)istate
->fsmonitor_dirty
->bit_size
, istate
->cache_nr
);
122 put_be32(&hdr_version
, INDEX_EXTENSION_VERSION2
);
123 strbuf_add(sb
, &hdr_version
, sizeof(uint32_t));
125 strbuf_addstr(sb
, istate
->fsmonitor_last_update
);
126 strbuf_addch(sb
, 0); /* Want to keep a NUL */
129 strbuf_add(sb
, &ewah_size
, sizeof(uint32_t)); /* we'll fix this up later */
131 ewah_start
= sb
->len
;
132 ewah_serialize_strbuf(istate
->fsmonitor_dirty
, sb
);
133 ewah_free(istate
->fsmonitor_dirty
);
134 istate
->fsmonitor_dirty
= NULL
;
136 /* fix up size field */
137 put_be32(&ewah_size
, sb
->len
- ewah_start
);
138 memcpy(sb
->buf
+ fixup
, &ewah_size
, sizeof(uint32_t));
140 trace2_data_string("index", NULL
, "extension/fsmn/write/token",
141 istate
->fsmonitor_last_update
);
142 trace_printf_key(&trace_fsmonitor
,
143 "write fsmonitor extension successful '%s'",
144 istate
->fsmonitor_last_update
);
148 * Call the query-fsmonitor hook passing the last update token of the saved results.
150 static int query_fsmonitor(int version
, const char *last_update
, struct strbuf
*query_result
)
152 struct child_process cp
= CHILD_PROCESS_INIT
;
158 strvec_push(&cp
.args
, core_fsmonitor
);
159 strvec_pushf(&cp
.args
, "%d", version
);
160 strvec_pushf(&cp
.args
, "%s", last_update
);
162 cp
.dir
= get_git_work_tree();
164 trace2_region_enter("fsm_hook", "query", NULL
);
166 result
= capture_command(&cp
, query_result
, 1024);
169 trace2_data_intmax("fsm_hook", NULL
, "query/failed", result
);
171 trace2_data_intmax("fsm_hook", NULL
, "query/response-length",
174 if (fsmonitor_is_trivial_response(query_result
))
175 trace2_data_intmax("fsm_hook", NULL
,
176 "query/trivial-response", 1);
179 trace2_region_leave("fsm_hook", "query", NULL
);
184 int fsmonitor_is_trivial_response(const struct strbuf
*query_result
)
186 static char trivial_response
[3] = { '\0', '/', '\0' };
187 int is_trivial
= !memcmp(trivial_response
,
188 &query_result
->buf
[query_result
->len
- 3], 3);
193 static void fsmonitor_refresh_callback(struct index_state
*istate
, char *name
)
195 int i
, len
= strlen(name
);
196 if (name
[len
- 1] == '/') {
199 * TODO We should binary search to find the first path with
200 * TODO this directory prefix. Then linearly update entries
201 * TODO while the prefix matches. Taking care to search without
202 * TODO the trailing slash -- because '/' sorts after a few
203 * TODO interesting special chars, like '.' and ' '.
206 /* Mark all entries for the folder invalid */
207 for (i
= 0; i
< istate
->cache_nr
; i
++) {
208 if (istate
->cache
[i
]->ce_flags
& CE_FSMONITOR_VALID
&&
209 starts_with(istate
->cache
[i
]->name
, name
))
210 istate
->cache
[i
]->ce_flags
&= ~CE_FSMONITOR_VALID
;
212 /* Need to remove the / from the path for the untracked cache */
213 name
[len
- 1] = '\0';
215 int pos
= index_name_pos(istate
, name
, strlen(name
));
218 struct cache_entry
*ce
= istate
->cache
[pos
];
219 ce
->ce_flags
&= ~CE_FSMONITOR_VALID
;
224 * Mark the untracked cache dirty even if it wasn't found in the index
225 * as it could be a new untracked file.
227 trace_printf_key(&trace_fsmonitor
, "fsmonitor_refresh_callback '%s'", name
);
228 untracked_cache_invalidate_path(istate
, name
, 0);
231 void refresh_fsmonitor(struct index_state
*istate
)
233 struct strbuf query_result
= STRBUF_INIT
;
234 int query_success
= 0, hook_version
= -1;
235 size_t bol
= 0; /* beginning of line */
236 uint64_t last_update
;
237 struct strbuf last_update_token
= STRBUF_INIT
;
241 if (!core_fsmonitor
|| istate
->fsmonitor_has_run_once
)
244 hook_version
= fsmonitor_hook_version();
246 istate
->fsmonitor_has_run_once
= 1;
248 trace_printf_key(&trace_fsmonitor
, "refresh fsmonitor");
250 * This could be racy so save the date/time now and query_fsmonitor
251 * should be inclusive to ensure we don't miss potential changes.
253 last_update
= getnanotime();
254 if (hook_version
== HOOK_INTERFACE_VERSION1
)
255 strbuf_addf(&last_update_token
, "%"PRIu64
"", last_update
);
258 * If we have a last update token, call query_fsmonitor for the set of
259 * changes since that token, else assume everything is possibly dirty
262 if (istate
->fsmonitor_last_update
) {
263 if (hook_version
== -1 || hook_version
== HOOK_INTERFACE_VERSION2
) {
264 query_success
= !query_fsmonitor(HOOK_INTERFACE_VERSION2
,
265 istate
->fsmonitor_last_update
, &query_result
);
268 if (hook_version
< 0)
269 hook_version
= HOOK_INTERFACE_VERSION2
;
272 * First entry will be the last update token
273 * Need to use a char * variable because static
274 * analysis was suggesting to use strbuf_addbuf
275 * but we don't want to copy the entire strbuf
276 * only the chars up to the first NUL
278 buf
= query_result
.buf
;
279 strbuf_addstr(&last_update_token
, buf
);
280 if (!last_update_token
.len
) {
281 warning("Empty last update token.");
284 bol
= last_update_token
.len
+ 1;
286 } else if (hook_version
< 0) {
287 hook_version
= HOOK_INTERFACE_VERSION1
;
288 if (!last_update_token
.len
)
289 strbuf_addf(&last_update_token
, "%"PRIu64
"", last_update
);
293 if (hook_version
== HOOK_INTERFACE_VERSION1
) {
294 query_success
= !query_fsmonitor(HOOK_INTERFACE_VERSION1
,
295 istate
->fsmonitor_last_update
, &query_result
);
298 trace_performance_since(last_update
, "fsmonitor process '%s'", core_fsmonitor
);
299 trace_printf_key(&trace_fsmonitor
, "fsmonitor process '%s' returned %s",
300 core_fsmonitor
, query_success
? "success" : "failure");
303 /* a fsmonitor process can return '/' to indicate all entries are invalid */
304 if (query_success
&& query_result
.buf
[bol
] != '/') {
305 /* Mark all entries returned by the monitor as dirty */
306 buf
= query_result
.buf
;
307 for (i
= bol
; i
< query_result
.len
; i
++) {
310 fsmonitor_refresh_callback(istate
, buf
+ bol
);
313 if (bol
< query_result
.len
)
314 fsmonitor_refresh_callback(istate
, buf
+ bol
);
316 /* Now mark the untracked cache for fsmonitor usage */
317 if (istate
->untracked
)
318 istate
->untracked
->use_fsmonitor
= 1;
321 /* We only want to run the post index changed hook if we've actually changed entries, so keep track
322 * if we actually changed entries or not */
323 int is_cache_changed
= 0;
324 /* Mark all entries invalid */
325 for (i
= 0; i
< istate
->cache_nr
; i
++) {
326 if (istate
->cache
[i
]->ce_flags
& CE_FSMONITOR_VALID
) {
327 is_cache_changed
= 1;
328 istate
->cache
[i
]->ce_flags
&= ~CE_FSMONITOR_VALID
;
332 /* If we're going to check every file, ensure we save the results */
333 if (is_cache_changed
)
334 istate
->cache_changed
|= FSMONITOR_CHANGED
;
336 if (istate
->untracked
)
337 istate
->untracked
->use_fsmonitor
= 0;
339 strbuf_release(&query_result
);
341 /* Now that we've updated istate, save the last_update_token */
342 FREE_AND_NULL(istate
->fsmonitor_last_update
);
343 istate
->fsmonitor_last_update
= strbuf_detach(&last_update_token
, NULL
);
347 * The caller wants to turn on FSMonitor. And when the caller writes
348 * the index to disk, a FSMonitor extension should be included. This
349 * requires that `istate->fsmonitor_last_update` not be NULL. But we
350 * have not actually talked to a FSMonitor process yet, so we don't
351 * have an initial value for this field.
353 * For a protocol V1 FSMonitor process, this field is a formatted
354 * "nanoseconds since epoch" field. However, for a protocol V2
355 * FSMonitor process, this field is an opaque token.
357 * Historically, `add_fsmonitor()` has initialized this field to the
358 * current time for protocol V1 processes. There are lots of race
359 * conditions here, but that code has shipped...
361 * The only true solution is to use a V2 FSMonitor and get a current
362 * or default token value (that it understands), but we cannot do that
363 * until we have actually talked to an instance of the FSMonitor process
364 * (but the protocol requires that we send a token first...).
366 * For simplicity, just initialize like we have a V1 process and require
367 * that V2 processes adapt.
369 static void initialize_fsmonitor_last_update(struct index_state
*istate
)
371 struct strbuf last_update
= STRBUF_INIT
;
373 strbuf_addf(&last_update
, "%"PRIu64
"", getnanotime());
374 istate
->fsmonitor_last_update
= strbuf_detach(&last_update
, NULL
);
377 void add_fsmonitor(struct index_state
*istate
)
381 if (!istate
->fsmonitor_last_update
) {
382 trace_printf_key(&trace_fsmonitor
, "add fsmonitor");
383 istate
->cache_changed
|= FSMONITOR_CHANGED
;
384 initialize_fsmonitor_last_update(istate
);
386 /* reset the fsmonitor state */
387 for (i
= 0; i
< istate
->cache_nr
; i
++)
388 istate
->cache
[i
]->ce_flags
&= ~CE_FSMONITOR_VALID
;
390 /* reset the untracked cache */
391 if (istate
->untracked
) {
392 add_untracked_cache(istate
);
393 istate
->untracked
->use_fsmonitor
= 1;
396 /* Update the fsmonitor state */
397 refresh_fsmonitor(istate
);
401 void remove_fsmonitor(struct index_state
*istate
)
403 if (istate
->fsmonitor_last_update
) {
404 trace_printf_key(&trace_fsmonitor
, "remove fsmonitor");
405 istate
->cache_changed
|= FSMONITOR_CHANGED
;
406 FREE_AND_NULL(istate
->fsmonitor_last_update
);
410 void tweak_fsmonitor(struct index_state
*istate
)
413 int fsmonitor_enabled
= git_config_get_fsmonitor();
415 if (istate
->fsmonitor_dirty
) {
416 if (fsmonitor_enabled
) {
417 /* Mark all entries valid */
418 for (i
= 0; i
< istate
->cache_nr
; i
++) {
419 istate
->cache
[i
]->ce_flags
|= CE_FSMONITOR_VALID
;
422 /* Mark all previously saved entries as dirty */
423 if (istate
->fsmonitor_dirty
->bit_size
> istate
->cache_nr
)
424 BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX
" > %u)",
425 (uintmax_t)istate
->fsmonitor_dirty
->bit_size
, istate
->cache_nr
);
426 ewah_each_bit(istate
->fsmonitor_dirty
, fsmonitor_ewah_callback
, istate
);
428 refresh_fsmonitor(istate
);
431 ewah_free(istate
->fsmonitor_dirty
);
432 istate
->fsmonitor_dirty
= NULL
;
435 switch (fsmonitor_enabled
) {
436 case -1: /* keep: do nothing */
439 remove_fsmonitor(istate
);
442 add_fsmonitor(istate
);
444 default: /* unknown value: do nothing */