From 40d934df72eaf244c826d5c26da0896ce7185cb6 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 5 Mar 2008 18:59:29 -0800 Subject: [PATCH] Make 'traverse_tree()' use linked structure rather than 'const char *base' This makes the calling convention a bit less obvious, but a lot more flexible. Instead of allocating and extending a new 'base' string, we just link the top-most name into a linked list of the 'info' structure when traversing a subdirectory, and we can generate the basename by following the list. Perhaps even more importantly, the linked list of info structures also gives us a place to naturally save off other information than just the directory name. Signed-off-by: Linus Torvalds Signed-off-by: Junio C Hamano --- merge-tree.c | 51 +++++++++++++++++++++++++++------------------------ tree-walk.c | 35 +++++++++++++++++++++++++++++++++-- tree-walk.h | 20 ++++++++++++++++++-- 3 files changed, 78 insertions(+), 28 deletions(-) diff --git a/merge-tree.c b/merge-tree.c index e08324686..a3511b76c 100644 --- a/merge-tree.c +++ b/merge-tree.c @@ -168,7 +168,13 @@ static struct merge_list *create_entry(unsigned stage, unsigned mode, const unsi return res; } -static void resolve(const char *base, struct name_entry *branch1, struct name_entry *result) +static char *traverse_path(const struct traverse_info *info, const struct name_entry *n) +{ + char *path = xmalloc(traverse_path_len(info, n) + 1); + return make_traverse_path(path, info, n); +} + +static void resolve(const struct traverse_info *info, struct name_entry *branch1, struct name_entry *result) { struct merge_list *orig, *final; const char *path; @@ -177,7 +183,7 @@ static void resolve(const char *base, struct name_entry *branch1, struct name_en if (!branch1) return; - path = xstrdup(mkpath("%s%s", base, result->path)); + path = traverse_path(info, result); orig = create_entry(2, branch1->mode, branch1->sha1, path); final = create_entry(0, result->mode, result->sha1, path); @@ -186,9 +192,8 @@ static void resolve(const char *base, struct name_entry *branch1, struct name_en add_merge_entry(final); } -static int unresolved_directory(const char *base, struct name_entry n[3]) +static int unresolved_directory(const struct traverse_info *info, struct name_entry n[3]) { - int baselen, pathlen; char *newbase; struct name_entry *p; struct tree_desc t[3]; @@ -204,13 +209,7 @@ static int unresolved_directory(const char *base, struct name_entry n[3]) } if (!S_ISDIR(p->mode)) return 0; - baselen = strlen(base); - pathlen = tree_entry_len(p->path, p->sha1); - newbase = xmalloc(baselen + pathlen + 2); - memcpy(newbase, base, baselen); - memcpy(newbase + baselen, p->path, pathlen); - memcpy(newbase + baselen + pathlen, "/", 2); - + newbase = traverse_path(info, p); buf0 = fill_tree_descriptor(t+0, n[0].sha1); buf1 = fill_tree_descriptor(t+1, n[1].sha1); buf2 = fill_tree_descriptor(t+2, n[2].sha1); @@ -224,7 +223,7 @@ static int unresolved_directory(const char *base, struct name_entry n[3]) } -static struct merge_list *link_entry(unsigned stage, const char *base, struct name_entry *n, struct merge_list *entry) +static struct merge_list *link_entry(unsigned stage, const struct traverse_info *info, struct name_entry *n, struct merge_list *entry) { const char *path; struct merge_list *link; @@ -234,17 +233,17 @@ static struct merge_list *link_entry(unsigned stage, const char *base, struct na if (entry) path = entry->path; else - path = xstrdup(mkpath("%s%s", base, n->path)); + path = traverse_path(info, n); link = create_entry(stage, n->mode, n->sha1, path); link->link = entry; return link; } -static void unresolved(const char *base, struct name_entry n[3]) +static void unresolved(const struct traverse_info *info, struct name_entry n[3]) { struct merge_list *entry = NULL; - if (unresolved_directory(base, n)) + if (unresolved_directory(info, n)) return; /* @@ -252,9 +251,9 @@ static void unresolved(const char *base, struct name_entry n[3]) * list has the stages in order - link_entry adds new * links at the front. */ - entry = link_entry(3, base, n + 2, entry); - entry = link_entry(2, base, n + 1, entry); - entry = link_entry(1, base, n + 0, entry); + entry = link_entry(3, info, n + 2, entry); + entry = link_entry(2, info, n + 1, entry); + entry = link_entry(1, info, n + 0, entry); add_merge_entry(entry); } @@ -288,36 +287,40 @@ static void unresolved(const char *base, struct name_entry n[3]) * The successful merge rules are the same as for the three-way merge * in git-read-tree. */ -static void threeway_callback(int n, unsigned long mask, struct name_entry *entry, const char *base) +static void threeway_callback(int n, unsigned long mask, struct name_entry *entry, struct traverse_info *info) { /* Same in both? */ if (same_entry(entry+1, entry+2)) { if (entry[0].sha1) { - resolve(base, NULL, entry+1); + resolve(info, NULL, entry+1); return; } } if (same_entry(entry+0, entry+1)) { if (entry[2].sha1 && !S_ISDIR(entry[2].mode)) { - resolve(base, entry+1, entry+2); + resolve(info, entry+1, entry+2); return; } } if (same_entry(entry+0, entry+2)) { if (entry[1].sha1 && !S_ISDIR(entry[1].mode)) { - resolve(base, NULL, entry+1); + resolve(info, NULL, entry+1); return; } } - unresolved(base, entry); + unresolved(info, entry); } static void merge_trees(struct tree_desc t[3], const char *base) { - traverse_trees(3, t, base, threeway_callback); + struct traverse_info info; + + setup_traverse_info(&info, base); + info.fn = threeway_callback; + traverse_trees(3, t, &info); } static void *get_tree_descriptor(struct tree_desc *desc, const char *rev) diff --git a/tree-walk.c b/tree-walk.c index 142205ddc..f9f7d225e 100644 --- a/tree-walk.c +++ b/tree-walk.c @@ -104,7 +104,38 @@ int tree_entry(struct tree_desc *desc, struct name_entry *entry) return 1; } -void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callback_t callback) +void setup_traverse_info(struct traverse_info *info, const char *base) +{ + int pathlen = strlen(base); + + memset(info, 0, sizeof(*info)); + if (pathlen && base[pathlen-1] == '/') + pathlen--; + info->pathlen = pathlen ? pathlen + 1 : 0; + info->name.path = base; + info->name.sha1 = (void *)(base + pathlen + 1); +} + +char *make_traverse_path(char *path, const struct traverse_info *info, const struct name_entry *n) +{ + int len = tree_entry_len(n->path, n->sha1); + int pathlen = info->pathlen; + + path[pathlen + len] = 0; + for (;;) { + memcpy(path + pathlen, n->path, len); + if (!pathlen) + break; + path[--pathlen] = '/'; + n = &info->name; + len = tree_entry_len(n->path, n->sha1); + info = info->prev; + pathlen -= len; + } + return path; +} + +void traverse_trees(int n, struct tree_desc *t, struct traverse_info *info) { struct name_entry *entry = xmalloc(n*sizeof(*entry)); @@ -150,7 +181,7 @@ void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callb } entry_clear(entry + i); } - callback(n, mask, entry, base); + info->fn(n, mask, entry, info); } free(entry); } diff --git a/tree-walk.h b/tree-walk.h index db0fbdc70..7c4ae646b 100644 --- a/tree-walk.h +++ b/tree-walk.h @@ -33,10 +33,26 @@ int tree_entry(struct tree_desc *, struct name_entry *); void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1); -typedef void (*traverse_callback_t)(int n, unsigned long mask, struct name_entry *entry, const char *base); +struct traverse_info; +typedef void (*traverse_callback_t)(int n, unsigned long mask, struct name_entry *entry, struct traverse_info *); +void traverse_trees(int n, struct tree_desc *t, struct traverse_info *info); -void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callback_t callback); +struct traverse_info { + struct traverse_info *prev; + struct name_entry name; + int pathlen; + + traverse_callback_t fn; + void *data; +}; int get_tree_entry(const unsigned char *, const char *, unsigned char *, unsigned *); +extern char *make_traverse_path(char *path, const struct traverse_info *info, const struct name_entry *n); +extern void setup_traverse_info(struct traverse_info *info, const char *base); + +static inline int traverse_path_len(const struct traverse_info *info, const struct name_entry *n) +{ + return info->pathlen + tree_entry_len(n->path, n->sha1); +} #endif -- 2.30.2