diff options
Diffstat (limited to 'third_party/git/attr.c')
| -rw-r--r-- | third_party/git/attr.c | 1159 |
1 files changed, 1159 insertions, 0 deletions
diff --git a/third_party/git/attr.c b/third_party/git/attr.c new file mode 100644 index 000000000000..93dc16b59cd6 --- /dev/null +++ b/third_party/git/attr.c @@ -0,0 +1,1159 @@ +/* + * Handle git attributes. See gitattributes(5) for a description of + * the file syntax, and Documentation/technical/api-gitattributes.txt + * for a description of the API. + * + * One basic design decision here is that we are not going to support + * an insanely large number of attributes. + */ + +#include "cache.h" +#include "config.h" +#include "exec-cmd.h" +#include "attr.h" +#include "dir.h" +#include "utf8.h" +#include "quote.h" +#include "thread-utils.h" + +const char git_attr__true[] = "(builtin)true"; +const char git_attr__false[] = "\0(builtin)false"; +static const char git_attr__unknown[] = "(builtin)unknown"; +#define ATTR__TRUE git_attr__true +#define ATTR__FALSE git_attr__false +#define ATTR__UNSET NULL +#define ATTR__UNKNOWN git_attr__unknown + +#ifndef DEBUG_ATTR +#define DEBUG_ATTR 0 +#endif + +struct git_attr { + int attr_nr; /* unique attribute number */ + char name[FLEX_ARRAY]; /* attribute name */ +}; + +const char *git_attr_name(const struct git_attr *attr) +{ + return attr->name; +} + +struct attr_hashmap { + struct hashmap map; + pthread_mutex_t mutex; +}; + +static inline void hashmap_lock(struct attr_hashmap *map) +{ + pthread_mutex_lock(&map->mutex); +} + +static inline void hashmap_unlock(struct attr_hashmap *map) +{ + pthread_mutex_unlock(&map->mutex); +} + +/* + * The global dictionary of all interned attributes. This + * is a singleton object which is shared between threads. + * Access to this dictionary must be surrounded with a mutex. + */ +static struct attr_hashmap g_attr_hashmap; + +/* The container for objects stored in "struct attr_hashmap" */ +struct attr_hash_entry { + struct hashmap_entry ent; /* must be the first member! */ + const char *key; /* the key; memory should be owned by value */ + size_t keylen; /* length of the key */ + void *value; /* the stored value */ +}; + +/* attr_hashmap comparison function */ +static int attr_hash_entry_cmp(const void *unused_cmp_data, + const void *entry, + const void *entry_or_key, + const void *unused_keydata) +{ + const struct attr_hash_entry *a = entry; + const struct attr_hash_entry *b = entry_or_key; + return (a->keylen != b->keylen) || strncmp(a->key, b->key, a->keylen); +} + +/* Initialize an 'attr_hashmap' object */ +static void attr_hashmap_init(struct attr_hashmap *map) +{ + hashmap_init(&map->map, attr_hash_entry_cmp, NULL, 0); +} + +/* + * Retrieve the 'value' stored in a hashmap given the provided 'key'. + * If there is no matching entry, return NULL. + */ +static void *attr_hashmap_get(struct attr_hashmap *map, + const char *key, size_t keylen) +{ + struct attr_hash_entry k; + struct attr_hash_entry *e; + + if (!map->map.tablesize) + attr_hashmap_init(map); + + hashmap_entry_init(&k, memhash(key, keylen)); + k.key = key; + k.keylen = keylen; + e = hashmap_get(&map->map, &k, NULL); + + return e ? e->value : NULL; +} + +/* Add 'value' to a hashmap based on the provided 'key'. */ +static void attr_hashmap_add(struct attr_hashmap *map, + const char *key, size_t keylen, + void *value) +{ + struct attr_hash_entry *e; + + if (!map->map.tablesize) + attr_hashmap_init(map); + + e = xmalloc(sizeof(struct attr_hash_entry)); + hashmap_entry_init(e, memhash(key, keylen)); + e->key = key; + e->keylen = keylen; + e->value = value; + + hashmap_add(&map->map, e); +} + +struct all_attrs_item { + const struct git_attr *attr; + const char *value; + /* + * If 'macro' is non-NULL, indicates that 'attr' is a macro based on + * the current attribute stack and contains a pointer to the match_attr + * definition of the macro + */ + const struct match_attr *macro; +}; + +/* + * Reallocate and reinitialize the array of all attributes (which is used in + * the attribute collection process) in 'check' based on the global dictionary + * of attributes. + */ +static void all_attrs_init(struct attr_hashmap *map, struct attr_check *check) +{ + int i; + unsigned int size; + + hashmap_lock(map); + + size = hashmap_get_size(&map->map); + if (size < check->all_attrs_nr) + BUG("interned attributes shouldn't be deleted"); + + /* + * If the number of attributes in the global dictionary has increased + * (or this attr_check instance doesn't have an initialized all_attrs + * field), reallocate the provided attr_check instance's all_attrs + * field and fill each entry with its corresponding git_attr. + */ + if (size != check->all_attrs_nr) { + struct attr_hash_entry *e; + struct hashmap_iter iter; + hashmap_iter_init(&map->map, &iter); + + REALLOC_ARRAY(check->all_attrs, size); + check->all_attrs_nr = size; + + while ((e = hashmap_iter_next(&iter))) { + const struct git_attr *a = e->value; + check->all_attrs[a->attr_nr].attr = a; + } + } + + hashmap_unlock(map); + + /* + * Re-initialize every entry in check->all_attrs. + * This re-initialization can live outside of the locked region since + * the attribute dictionary is no longer being accessed. + */ + for (i = 0; i < check->all_attrs_nr; i++) { + check->all_attrs[i].value = ATTR__UNKNOWN; + check->all_attrs[i].macro = NULL; + } +} + +static int attr_name_valid(const char *name, size_t namelen) +{ + /* + * Attribute name cannot begin with '-' and must consist of + * characters from [-A-Za-z0-9_.]. + */ + if (namelen <= 0 || *name == '-') + return 0; + while (namelen--) { + char ch = *name++; + if (! (ch == '-' || ch == '.' || ch == '_' || + ('0' <= ch && ch <= '9') || + ('a' <= ch && ch <= 'z') || + ('A' <= ch && ch <= 'Z')) ) + return 0; + } + return 1; +} + +static void report_invalid_attr(const char *name, size_t len, + const char *src, int lineno) +{ + struct strbuf err = STRBUF_INIT; + strbuf_addf(&err, _("%.*s is not a valid attribute name"), + (int) len, name); + fprintf(stderr, "%s: %s:%d\n", err.buf, src, lineno); + strbuf_release(&err); +} + +/* + * Given a 'name', lookup and return the corresponding attribute in the global + * dictionary. If no entry is found, create a new attribute and store it in + * the dictionary. + */ +static const struct git_attr *git_attr_internal(const char *name, int namelen) +{ + struct git_attr *a; + + if (!attr_name_valid(name, namelen)) + return NULL; + + hashmap_lock(&g_attr_hashmap); + + a = attr_hashmap_get(&g_attr_hashmap, name, namelen); + + if (!a) { + FLEX_ALLOC_MEM(a, name, name, namelen); + a->attr_nr = hashmap_get_size(&g_attr_hashmap.map); + + attr_hashmap_add(&g_attr_hashmap, a->name, namelen, a); + assert(a->attr_nr == + (hashmap_get_size(&g_attr_hashmap.map) - 1)); + } + + hashmap_unlock(&g_attr_hashmap); + + return a; +} + +const struct git_attr *git_attr(const char *name) +{ + return git_attr_internal(name, strlen(name)); +} + +/* What does a matched pattern decide? */ +struct attr_state { + const struct git_attr *attr; + const char *setto; +}; + +struct pattern { + const char *pattern; + int patternlen; + int nowildcardlen; + unsigned flags; /* EXC_FLAG_* */ +}; + +/* + * One rule, as from a .gitattributes file. + * + * If is_macro is true, then u.attr is a pointer to the git_attr being + * defined. + * + * If is_macro is false, then u.pat is the filename pattern to which the + * rule applies. + * + * In either case, num_attr is the number of attributes affected by + * this rule, and state is an array listing them. The attributes are + * listed as they appear in the file (macros unexpanded). + */ +struct match_attr { + union { + struct pattern pat; + const struct git_attr *attr; + } u; + char is_macro; + unsigned num_attr; + struct attr_state state[FLEX_ARRAY]; +}; + +static const char blank[] = " \t\r\n"; + +/* + * Parse a whitespace-delimited attribute state (i.e., "attr", + * "-attr", "!attr", or "attr=value") from the string starting at src. + * If e is not NULL, write the results to *e. Return a pointer to the + * remainder of the string (with leading whitespace removed), or NULL + * if there was an error. + */ +static const char *parse_attr(const char *src, int lineno, const char *cp, + struct attr_state *e) +{ + const char *ep, *equals; + int len; + + ep = cp + strcspn(cp, blank); + equals = strchr(cp, '='); + if (equals && ep < equals) + equals = NULL; + if (equals) + len = equals - cp; + else + len = ep - cp; + if (!e) { + if (*cp == '-' || *cp == '!') { + cp++; + len--; + } + if (!attr_name_valid(cp, len)) { + report_invalid_attr(cp, len, src, lineno); + return NULL; + } + } else { + /* + * As this function is always called twice, once with + * e == NULL in the first pass and then e != NULL in + * the second pass, no need for attr_name_valid() + * check here. + */ + if (*cp == '-' || *cp == '!') { + e->setto = (*cp == '-') ? ATTR__FALSE : ATTR__UNSET; + cp++; + len--; + } + else if (!equals) + e->setto = ATTR__TRUE; + else { + e->setto = xmemdupz(equals + 1, ep - equals - 1); + } + e->attr = git_attr_internal(cp, len); + } + return ep + strspn(ep, blank); +} + +static struct match_attr *parse_attr_line(const char *line, const char *src, + int lineno, int macro_ok) +{ + int namelen; + int num_attr, i; + const char *cp, *name, *states; + struct match_attr *res = NULL; + int is_macro; + struct strbuf pattern = STRBUF_INIT; + + cp = line + strspn(line, blank); + if (!*cp || *cp == '#') + return NULL; + name = cp; + + if (*cp == '"' && !unquote_c_style(&pattern, name, &states)) { + name = pattern.buf; + namelen = pattern.len; + } else { + namelen = strcspn(name, blank); + states = name + namelen; + } + + if (strlen(ATTRIBUTE_MACRO_PREFIX) < namelen && + starts_with(name, ATTRIBUTE_MACRO_PREFIX)) { + if (!macro_ok) { + fprintf_ln(stderr, _("%s not allowed: %s:%d"), + name, src, lineno); + goto fail_return; + } + is_macro = 1; + name += strlen(ATTRIBUTE_MACRO_PREFIX); + name += strspn(name, blank); + namelen = strcspn(name, blank); + if (!attr_name_valid(name, namelen)) { + report_invalid_attr(name, namelen, src, lineno); + goto fail_return; + } + } + else + is_macro = 0; + + states += strspn(states, blank); + + /* First pass to count the attr_states */ + for (cp = states, num_attr = 0; *cp; num_attr++) { + cp = parse_attr(src, lineno, cp, NULL); + if (!cp) + goto fail_return; + } + + res = xcalloc(1, + sizeof(*res) + + sizeof(struct attr_state) * num_attr + + (is_macro ? 0 : namelen + 1)); + if (is_macro) { + res->u.attr = git_attr_internal(name, namelen); + } else { + char *p = (char *)&(res->state[num_attr]); + memcpy(p, name, namelen); + res->u.pat.pattern = p; + parse_exclude_pattern(&res->u.pat.pattern, + &res->u.pat.patternlen, + &res->u.pat.flags, + &res->u.pat.nowildcardlen); + if (res->u.pat.flags & EXC_FLAG_NEGATIVE) { + warning(_("Negative patterns are ignored in git attributes\n" + "Use '\\!' for literal leading exclamation.")); + goto fail_return; + } + } + res->is_macro = is_macro; + res->num_attr = num_attr; + + /* Second pass to fill the attr_states */ + for (cp = states, i = 0; *cp; i++) { + cp = parse_attr(src, lineno, cp, &(res->state[i])); + } + + strbuf_release(&pattern); + return res; + +fail_return: + strbuf_release(&pattern); + free(res); + return NULL; +} + +/* + * Like info/exclude and .gitignore, the attribute information can + * come from many places. + * + * (1) .gitattributes file of the same directory; + * (2) .gitattributes file of the parent directory if (1) does not have + * any match; this goes recursively upwards, just like .gitignore. + * (3) $GIT_DIR/info/attributes, which overrides both of the above. + * + * In the same file, later entries override the earlier match, so in the + * global list, we would have entries from info/attributes the earliest + * (reading the file from top to bottom), .gitattributes of the root + * directory (again, reading the file from top to bottom) down to the + * current directory, and then scan the list backwards to find the first match. + * This is exactly the same as what is_excluded() does in dir.c to deal with + * .gitignore file and info/excludes file as a fallback. + */ + +struct attr_stack { + struct attr_stack *prev; + char *origin; + size_t originlen; + unsigned num_matches; + unsigned alloc; + struct match_attr **attrs; +}; + +static void attr_stack_free(struct attr_stack *e) +{ + int i; + free(e->origin); + for (i = 0; i < e->num_matches; i++) { + struct match_attr *a = e->attrs[i]; + int j; + for (j = 0; j < a->num_attr; j++) { + const char *setto = a->state[j].setto; + if (setto == ATTR__TRUE || + setto == ATTR__FALSE || + setto == ATTR__UNSET || + setto == ATTR__UNKNOWN) + ; + else + free((char *) setto); + } + free(a); + } + free(e->attrs); + free(e); +} + +static void drop_attr_stack(struct attr_stack **stack) +{ + while (*stack) { + struct attr_stack *elem = *stack; + *stack = elem->prev; + attr_stack_free(elem); + } +} + +/* List of all attr_check structs; access should be surrounded by mutex */ +static struct check_vector { + size_t nr; + size_t alloc; + struct attr_check **checks; + pthread_mutex_t mutex; +} check_vector; + +static inline void vector_lock(void) +{ + pthread_mutex_lock(&check_vector.mutex); +} + +static inline void vector_unlock(void) +{ + pthread_mutex_unlock(&check_vector.mutex); +} + +static void check_vector_add(struct attr_check *c) +{ + vector_lock(); + + ALLOC_GROW(check_vector.checks, + check_vector.nr + 1, + check_vector.alloc); + check_vector.checks[check_vector.nr++] = c; + + vector_unlock(); +} + +static void check_vector_remove(struct attr_check *check) +{ + int i; + + vector_lock(); + + /* Find entry */ + for (i = 0; i < check_vector.nr; i++) + if (check_vector.checks[i] == check) + break; + + if (i >= check_vector.nr) + BUG("no entry found"); + + /* shift entries over */ + for (; i < check_vector.nr - 1; i++) + check_vector.checks[i] = check_vector.checks[i + 1]; + + check_vector.nr--; + + vector_unlock(); +} + +/* Iterate through all attr_check instances and drop their stacks */ +static void drop_all_attr_stacks(void) +{ + int i; + + vector_lock(); + + for (i = 0; i < check_vector.nr; i++) { + drop_attr_stack(&check_vector.checks[i]->stack); + } + + vector_unlock(); +} + +struct attr_check *attr_check_alloc(void) +{ + struct attr_check *c = xcalloc(1, sizeof(struct attr_check)); + + /* save pointer to the check struct */ + check_vector_add(c); + + return c; +} + +struct attr_check *attr_check_initl(const char *one, ...) +{ + struct attr_check *check; + int cnt; + va_list params; + const char *param; + + va_start(params, one); + for (cnt = 1; (param = va_arg(params, const char *)) != NULL; cnt++) + ; + va_end(params); + + check = attr_check_alloc(); + check->nr = cnt; + check->alloc = cnt; + check->items = xcalloc(cnt, sizeof(struct attr_check_item)); + + check->items[0].attr = git_attr(one); + va_start(params, one); + for (cnt = 1; cnt < check->nr; cnt++) { + const struct git_attr *attr; + param = va_arg(params, const char *); + if (!param) + BUG("counted %d != ended at %d", + check->nr, cnt); + attr = git_attr(param); + if (!attr) + BUG("%s: not a valid attribute name", param); + check->items[cnt].attr = attr; + } + va_end(params); + return check; +} + +struct attr_check *attr_check_dup(const struct attr_check *check) +{ + struct attr_check *ret; + + if (!check) + return NULL; + + ret = attr_check_alloc(); + + ret->nr = check->nr; + ret->alloc = check->alloc; + ALLOC_ARRAY(ret->items, ret->nr); + COPY_ARRAY(ret->items, check->items, ret->nr); + + return ret; +} + +struct attr_check_item *attr_check_append(struct attr_check *check, + const struct git_attr *attr) +{ + struct attr_check_item *item; + + ALLOC_GROW(check->items, check->nr + 1, check->alloc); + item = &check->items[check->nr++]; + item->attr = attr; + return item; +} + +void attr_check_reset(struct attr_check *check) +{ + check->nr = 0; +} + +void attr_check_clear(struct attr_check *check) +{ + FREE_AND_NULL(check->items); + check->alloc = 0; + check->nr = 0; + + FREE_AND_NULL(check->all_attrs); + check->all_attrs_nr = 0; + + drop_attr_stack(&check->stack); +} + +void attr_check_free(struct attr_check *check) +{ + if (check) { + /* Remove check from the check vector */ + check_vector_remove(check); + + attr_check_clear(check); + free(check); + } +} + +static const char *builtin_attr[] = { + "[attr]binary -diff -merge -text", + NULL, +}; + +static void handle_attr_line(struct attr_stack *res, + const char *line, + const char *src, + int lineno, + int macro_ok) +{ + struct match_attr *a; + + a = parse_attr_line(line, src, lineno, macro_ok); + if (!a) + return; + ALLOC_GROW(res->attrs, res->num_matches + 1, res->alloc); + res->attrs[res->num_matches++] = a; +} + +static struct attr_stack *read_attr_from_array(const char **list) +{ + struct attr_stack *res; + const char *line; + int lineno = 0; + + res = xcalloc(1, sizeof(*res)); + while ((line = *(list++)) != NULL) + handle_attr_line(res, line, "[builtin]", ++lineno, 1); + return res; +} + +/* + * Callers into the attribute system assume there is a single, system-wide + * global state where attributes are read from and when the state is flipped by + * calling git_attr_set_direction(), the stack frames that have been + * constructed need to be discarded so so that subsequent calls into the + * attribute system will lazily read from the right place. Since changing + * direction causes a global paradigm shift, it should not ever be called while + * another thread could potentially be calling into the attribute system. + */ +static enum git_attr_direction direction; + +void git_attr_set_direction(enum git_attr_direction new_direction) +{ + if (is_bare_repository() && new_direction != GIT_ATTR_INDEX) + BUG("non-INDEX attr direction in a bare repo"); + + if (new_direction != direction) + drop_all_attr_stacks(); + + direction = new_direction; +} + +static struct attr_stack *read_attr_from_file(const char *path, int macro_ok) +{ + FILE *fp = fopen_or_warn(path, "r"); + struct attr_stack *res; + char buf[2048]; + int lineno = 0; + + if (!fp) + return NULL; + res = xcalloc(1, sizeof(*res)); + while (fgets(buf, sizeof(buf), fp)) { + char *bufp = buf; + if (!lineno) + skip_utf8_bom(&bufp, strlen(bufp)); + handle_attr_line(res, bufp, path, ++lineno, macro_ok); + } + fclose(fp); + return res; +} + +static struct attr_stack *read_attr_from_index(const struct index_state *istate, + const char *path, + int macro_ok) +{ + struct attr_stack *res; + char *buf, *sp; + int lineno = 0; + + if (!istate) + return NULL; + + buf = read_blob_data_from_index(istate, path, NULL); + if (!buf) + return NULL; + + res = xcalloc(1, sizeof(*res)); + for (sp = buf; *sp; ) { + char *ep; + int more; + + ep = strchrnul(sp, '\n'); + more = (*ep == '\n'); + *ep = '\0'; + handle_attr_line(res, sp, path, ++lineno, macro_ok); + sp = ep + more; + } + free(buf); + return res; +} + +static struct attr_stack *read_attr(const struct index_state *istate, + const char *path, int macro_ok) +{ + struct attr_stack *res = NULL; + + if (direction == GIT_ATTR_INDEX) { + res = read_attr_from_index(istate, path, macro_ok); + } else if (!is_bare_repository()) { + if (direction == GIT_ATTR_CHECKOUT) { + res = read_attr_from_index(istate, path, macro_ok); + if (!res) + res = read_attr_from_file(path, macro_ok); + } else if (direction == GIT_ATTR_CHECKIN) { + res = read_attr_from_file(path, macro_ok); + if (!res) + /* + * There is no checked out .gitattributes file + * there, but we might have it in the index. + * We allow operation in a sparsely checked out + * work tree, so read from it. + */ + res = read_attr_from_index(istate, path, macro_ok); + } + } + + if (!res) + res = xcalloc(1, sizeof(*res)); + return res; +} + +#if DEBUG_ATTR +static void debug_info(const char *what, struct attr_stack *elem) +{ + fprintf(stderr, "%s: %s\n", what, elem->origin ? elem->origin : "()"); +} +static void debug_set(const char *what, const char *match, struct git_attr *attr, const void *v) +{ + const char *value = v; + + if (ATTR_TRUE(value)) + value = "set"; + else if (ATTR_FALSE(value)) + value = "unset"; + else if (ATTR_UNSET(value)) + value = "unspecified"; + + fprintf(stderr, "%s: %s => %s (%s)\n", + what, attr->name, (char *) value, match); +} +#define debug_push(a) debug_info("push", (a)) +#define debug_pop(a) debug_info("pop", (a)) +#else +#define debug_push(a) do { ; } while (0) +#define debug_pop(a) do { ; } while (0) +#define debug_set(a,b,c,d) do { ; } while (0) +#endif /* DEBUG_ATTR */ + +static const char *git_etc_gitattributes(void) +{ + static const char *system_wide; + if (!system_wide) + system_wide = system_path(ETC_GITATTRIBUTES); + return system_wide; +} + +static const char *get_home_gitattributes(void) +{ + if (!git_attributes_file) + git_attributes_file = xdg_config_home("attributes"); + + return git_attributes_file; +} + +static int git_attr_system(void) +{ + return !git_env_bool("GIT_ATTR_NOSYSTEM", 0); +} + +static GIT_PATH_FUNC(git_path_info_attributes, INFOATTRIBUTES_FILE) + +static void push_stack(struct attr_stack **attr_stack_p, + struct attr_stack *elem, char *origin, size_t originlen) +{ + if (elem) { + elem->origin = origin; + if (origin) + elem->originlen = originlen; + elem->prev = *attr_stack_p; + *attr_stack_p = elem; + } +} + +static void bootstrap_attr_stack(const struct index_state *istate, + struct attr_stack **stack) +{ + struct attr_stack *e; + + if (*stack) + return; + + /* builtin frame */ + e = read_attr_from_array(builtin_attr); + push_stack(stack, e, NULL, 0); + + /* system-wide frame */ + if (git_attr_system()) { + e = read_attr_from_file(git_etc_gitattributes(), 1); + push_stack(stack, e, NULL, 0); + } + + /* home directory */ + if (get_home_gitattributes()) { + e = read_attr_from_file(get_home_gitattributes(), 1); + push_stack(stack, e, NULL, 0); + } + + /* root directory */ + e = read_attr(istate, GITATTRIBUTES_FILE, 1); + push_stack(stack, e, xstrdup(""), 0); + + /* info frame */ + if (startup_info->have_repository) + e = read_attr_from_file(git_path_info_attributes(), 1); + else + e = NULL; + if (!e) + e = xcalloc(1, sizeof(struct attr_stack)); + push_stack(stack, e, NULL, 0); +} + +static void prepare_attr_stack(const struct index_state *istate, + const char *path, int dirlen, + struct attr_stack **stack) +{ + struct attr_stack *info; + struct strbuf pathbuf = STRBUF_INIT; + + /* + * At the bottom of the attribute stack is the built-in + * set of attribute definitions, followed by the contents + * of $(prefix)/etc/gitattributes and a file specified by + * core.attributesfile. Then, contents from + * .gitattributes files from directories closer to the + * root to the ones in deeper directories are pushed + * to the stack. Finally, at the very top of the stack + * we always keep the contents of $GIT_DIR/info/attributes. + * + * When checking, we use entries from near the top of the + * stack, preferring $GIT_DIR/info/attributes, then + * .gitattributes in deeper directories to shallower ones, + * and finally use the built-in set as the default. + */ + bootstrap_attr_stack(istate, stack); + + /* + * Pop the "info" one that is always at the top of the stack. + */ + info = *stack; + *stack = info->prev; + + /* + * Pop the ones from directories that are not the prefix of + * the path we are checking. Break out of the loop when we see + * the root one (whose origin is an empty string "") or the builtin + * one (whose origin is NULL) without popping it. + */ + while ((*stack)->origin) { + int namelen = (*stack)->originlen; + struct attr_stack *elem; + + elem = *stack; + if (namelen <= dirlen && + !strncmp(elem->origin, path, namelen) && + (!namelen || path[namelen] == '/')) + break; + + debug_pop(elem); + *stack = elem->prev; + attr_stack_free(elem); + } + + /* + * bootstrap_attr_stack() should have added, and the + * above loop should have stopped before popping, the + * root element whose attr_stack->origin is set to an + * empty string. + */ + assert((*stack)->origin); + + strbuf_addstr(&pathbuf, (*stack)->origin); + /* Build up to the directory 'path' is in */ + while (pathbuf.len < dirlen) { + size_t len = pathbuf.len; + struct attr_stack *next; + char *origin; + + /* Skip path-separator */ + if (len < dirlen && is_dir_sep(path[len])) + len++; + /* Find the end of the next component */ + while (len < dirlen && !is_dir_sep(path[len])) + len++; + + if (pathbuf.len > 0) + strbuf_addch(&pathbuf, '/'); + strbuf_add(&pathbuf, path + pathbuf.len, (len - pathbuf.len)); + strbuf_addf(&pathbuf, "/%s", GITATTRIBUTES_FILE); + + next = read_attr(istate, pathbuf.buf, 0); + + /* reset the pathbuf to not include "/.gitattributes" */ + strbuf_setlen(&pathbuf, len); + + origin = xstrdup(pathbuf.buf); + push_stack(stack, next, origin, len); + } + + /* + * Finally push the "info" one at the top of the stack. + */ + push_stack(stack, info, NULL, 0); + + strbuf_release(&pathbuf); +} + +static int path_matches(const char *pathname, int pathlen, + int basename_offset, + const struct pattern *pat, + const char *base, int baselen) +{ + const char *pattern = pat->pattern; + int prefix = pat->nowildcardlen; + int isdir = (pathlen && pathname[pathlen - 1] == '/'); + + if ((pat->flags & EXC_FLAG_MUSTBEDIR) && !isdir) + return 0; + + if (pat->flags & EXC_FLAG_NODIR) { + return match_basename(pathname + basename_offset, + pathlen - basename_offset - isdir, + pattern, prefix, + pat->patternlen, pat->flags); + } + return match_pathname(pathname, pathlen - isdir, + base, baselen, + pattern, prefix, pat->patternlen, pat->flags); +} + +static int macroexpand_one(struct all_attrs_item *all_attrs, int nr, int rem); + +static int fill_one(const char *what, struct all_attrs_item *all_attrs, + const struct match_attr *a, int rem) +{ + int i; + + for (i = a->num_attr - 1; rem > 0 && i >= 0; i--) { + const struct git_attr *attr = a->state[i].attr; + const char **n = &(all_attrs[attr->attr_nr].value); + const char *v = a->state[i].setto; + + if (*n == ATTR__UNKNOWN) { + debug_set(what, + a->is_macro ? a->u.attr->name : a->u.pat.pattern, + attr, v); + *n = v; + rem--; + rem = macroexpand_one(all_attrs, attr->attr_nr, rem); + } + } + return rem; +} + +static int fill(const char *path, int pathlen, int basename_offset, + const struct attr_stack *stack, + struct all_attrs_item *all_attrs, int rem) +{ + for (; rem > 0 && stack; stack = stack->prev) { + int i; + const char *base = stack->origin ? stack->origin : ""; + + for (i = stack->num_matches - 1; 0 < rem && 0 <= i; i--) { + const struct match_attr *a = stack->attrs[i]; + if (a->is_macro) + continue; + if (path_matches(path, pathlen, basename_offset, + &a->u.pat, base, stack->originlen)) + rem = fill_one("fill", all_attrs, a, rem); + } + } + + return rem; +} + +static int macroexpand_one(struct all_attrs_item *all_attrs, int nr, int rem) +{ + const struct all_attrs_item *item = &all_attrs[nr]; + + if (item->macro && item->value == ATTR__TRUE) + return fill_one("expand", all_attrs, item->macro, rem); + else + return rem; +} + +/* + * Marks the attributes which are macros based on the attribute stack. + * This prevents having to search through the attribute stack each time + * a macro needs to be expanded during the fill stage. + */ +static void determine_macros(struct all_attrs_item *all_attrs, + const struct attr_stack *stack) +{ + for (; stack; stack = stack->prev) { + int i; + for (i = stack->num_matches - 1; i >= 0; i--) { + const struct match_attr *ma = stack->attrs[i]; + if (ma->is_macro) { + int n = ma->u.attr->attr_nr; + if (!all_attrs[n].macro) { + all_attrs[n].macro = ma; + } + } + } + } +} + +/* + * Collect attributes for path into the array pointed to by check->all_attrs. + * If check->check_nr is non-zero, only attributes in check[] are collected. + * Otherwise all attributes are collected. + */ +static void collect_some_attrs(const struct index_state *istate, + const char *path, + struct attr_check *check) +{ + int pathlen, rem, dirlen; + const char *cp, *last_slash = NULL; + int basename_offset; + + for (cp = path; *cp; cp++) { + if (*cp == '/' && cp[1]) + last_slash = cp; + } + pathlen = cp - path; + if (last_slash) { + basename_offset = last_slash + 1 - path; + dirlen = last_slash - path; + } else { + basename_offset = 0; + dirlen = 0; + } + + prepare_attr_stack(istate, path, dirlen, &check->stack); + all_attrs_init(&g_attr_hashmap, check); + determine_macros(check->all_attrs, check->stack); + + rem = check->all_attrs_nr; + fill(path, pathlen, basename_offset, check->stack, check->all_attrs, rem); +} + +void git_check_attr(const struct index_state *istate, + const char *path, + struct attr_check *check) +{ + int i; + + collect_some_attrs(istate, path, check); + + for (i = 0; i < check->nr; i++) { + size_t n = check->items[i].attr->attr_nr; + const char *value = check->all_attrs[n].value; + if (value == ATTR__UNKNOWN) + value = ATTR__UNSET; + check->items[i].value = value; + } +} + +void git_all_attrs(const struct index_state *istate, + const char *path, struct attr_check *check) +{ + int i; + + attr_check_reset(check); + collect_some_attrs(istate, path, check); + + for (i = 0; i < check->all_attrs_nr; i++) { + const char *name = check->all_attrs[i].attr->name; + const char *value = check->all_attrs[i].value; + struct attr_check_item *item; + if (value == ATTR__UNSET || value == ATTR__UNKNOWN) + continue; + item = attr_check_append(check, git_attr(name)); + item->value = value; + } +} + +void attr_start(void) +{ + pthread_mutex_init(&g_attr_hashmap.mutex, NULL); + pthread_mutex_init(&check_vector.mutex, NULL); +} |