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-rw-r--r--attr.c1150
1 files changed, 1150 insertions, 0 deletions
diff --git a/attr.c b/attr.c
new file mode 100644
index 0000000..4ef85d6
--- /dev/null
+++ b/attr.c
@@ -0,0 +1,1150 @@
+/*
+ * Handle git attributes. See gitattributes(5) for a description of
+ * the file syntax, and attr.h 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 container for objects stored in "struct attr_hashmap" */
+struct attr_hash_entry {
+ struct hashmap_entry ent;
+ 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 struct hashmap_entry *eptr,
+ const struct hashmap_entry *entry_or_key,
+ const void *unused_keydata)
+{
+ const struct attr_hash_entry *a, *b;
+
+ a = container_of(eptr, const struct attr_hash_entry, ent);
+ b = container_of(entry_or_key, const struct attr_hash_entry, ent);
+ return (a->keylen != b->keylen) || strncmp(a->key, b->key, a->keylen);
+}
+
+/*
+ * 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 = {
+ HASHMAP_INIT(attr_hash_entry_cmp, NULL)
+};
+
+/*
+ * 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;
+
+ hashmap_entry_init(&k.ent, memhash(key, keylen));
+ k.key = key;
+ k.keylen = keylen;
+ e = hashmap_get_entry(&map->map, &k, ent, 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;
+
+ e = xmalloc(sizeof(struct attr_hash_entry));
+ hashmap_entry_init(&e->ent, memhash(key, keylen));
+ e->key = key;
+ e->keylen = keylen;
+ e->value = value;
+
+ hashmap_add(&map->map, &e->ent);
+}
+
+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;
+
+ REALLOC_ARRAY(check->all_attrs, size);
+ check->all_attrs_nr = size;
+
+ hashmap_for_each_entry(&map->map, &iter, e,
+ ent /* member name */) {
+ 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; /* PATTERN_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_path_pattern(&res->u.pat.pattern,
+ &res->u.pat.patternlen,
+ &res->u.pat.flags,
+ &res->u.pat.nowildcardlen);
+ if (res->u.pat.flags & PATTERN_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 & PATTERN_FLAG_MUSTBEDIR) && !isdir)
+ return 0;
+
+ if (pat->flags & PATTERN_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);
+}