Documentation/git-sh-setup.txt: programmer's docs
[gitweb.git] / refs.c
diff --git a/refs.c b/refs.c
index 96ea8b6907b1e4be9c7b8575ff7e4a36f5a7a5f8..7d858637c438f3938af3cf7a8d592cef1fa3bd43 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -1,10 +1,8 @@
-#include "refs.h"
 #include "cache.h"
+#include "refs.h"
 #include "object.h"
 #include "tag.h"
 
-#include <errno.h>
-
 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
 #define REF_KNOWS_PEELED 04
 
@@ -286,7 +284,7 @@ const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *
                fd = open(path, O_RDONLY);
                if (fd < 0)
                        return NULL;
-               len = read(fd, buffer, sizeof(buffer)-1);
+               len = read_in_full(fd, buffer, sizeof(buffer)-1);
                close(fd);
 
                /*
@@ -334,7 +332,7 @@ int create_symref(const char *ref_target, const char *refs_heads_master)
        }
        lockpath = mkpath("%s.lock", git_HEAD);
        fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666); 
-       written = write(fd, ref, len);
+       written = write_in_full(fd, ref, len);
        close(fd);
        if (written != len) {
                unlink(lockpath);
@@ -534,7 +532,7 @@ int check_ref_format(const char *ref)
                level++;
                if (!ch) {
                        if (level < 2)
-                               return -1; /* at least of form "heads/blah" */
+                               return -2; /* at least of form "heads/blah" */
                        return 0;
                }
        }
@@ -610,6 +608,29 @@ static int remove_empty_directories(char *file)
        return remove_empty_dir_recursive(path, len);
 }
 
+static int is_refname_available(const char *ref, const char *oldref,
+                               struct ref_list *list, int quiet)
+{
+       int namlen = strlen(ref); /* e.g. 'foo/bar' */
+       while (list) {
+               /* list->name could be 'foo' or 'foo/bar/baz' */
+               if (!oldref || strcmp(oldref, list->name)) {
+                       int len = strlen(list->name);
+                       int cmplen = (namlen < len) ? namlen : len;
+                       const char *lead = (namlen < len) ? list->name : ref;
+                       if (!strncmp(ref, list->name, cmplen) &&
+                           lead[cmplen] == '/') {
+                               if (!quiet)
+                                       error("'%s' exists; cannot create '%s'",
+                                             list->name, ref);
+                               return 0;
+                       }
+               }
+               list = list->next;
+       }
+       return 1;
+}
+
 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int *flag)
 {
        char *ref_file;
@@ -643,29 +664,14 @@ static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char
                        orig_ref, strerror(errno));
                goto error_return;
        }
-       if (is_null_sha1(lock->old_sha1)) {
-               /* The ref did not exist and we are creating it.
-                * Make sure there is no existing ref that is packed
-                * whose name begins with our refname, nor a ref whose
-                * name is a proper prefix of our refname.
-                */
-               int namlen = strlen(ref); /* e.g. 'foo/bar' */
-               struct ref_list *list = get_packed_refs();
-               while (list) {
-                       /* list->name could be 'foo' or 'foo/bar/baz' */
-                       int len = strlen(list->name);
-                       int cmplen = (namlen < len) ? namlen : len;
-                       const char *lead = (namlen < len) ? list->name : ref;
-
-                       if (!strncmp(ref, list->name, cmplen) &&
-                           lead[cmplen] == '/') {
-                               error("'%s' exists; cannot create '%s'",
-                                     list->name, ref);
-                               goto error_return;
-                       }
-                       list = list->next;
-               }
-       }
+       /* When the ref did not exist and we are creating it,
+        * make sure there is no existing ref that is packed
+        * whose name begins with our refname, nor a ref whose
+        * name is a proper prefix of our refname.
+        */
+       if (is_null_sha1(lock->old_sha1) &&
+            !is_refname_available(ref, NULL, get_packed_refs(), 0))
+               goto error_return;
 
        lock->lk = xcalloc(1, sizeof(struct lock_file));
 
@@ -720,7 +726,6 @@ static int repack_without_ref(const char *refname)
        }
        if (!found)
                return 0;
-       memset(&packlock, 0, sizeof(packlock));
        fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
        if (fd < 0)
                return error("cannot delete '%s' from packed refs", refname);
@@ -776,6 +781,132 @@ int delete_ref(const char *refname, unsigned char *sha1)
        return ret;
 }
 
+int rename_ref(const char *oldref, const char *newref, const char *logmsg)
+{
+       static const char renamed_ref[] = "RENAMED-REF";
+       unsigned char sha1[20], orig_sha1[20];
+       int flag = 0, logmoved = 0;
+       struct ref_lock *lock;
+       struct stat loginfo;
+       int log = !lstat(git_path("logs/%s", oldref), &loginfo);
+
+       if (S_ISLNK(loginfo.st_mode))
+               return error("reflog for %s is a symlink", oldref);
+
+       if (!resolve_ref(oldref, orig_sha1, 1, &flag))
+               return error("refname %s not found", oldref);
+
+       if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
+               return 1;
+
+       if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
+               return 1;
+
+       lock = lock_ref_sha1_basic(renamed_ref, NULL, NULL);
+       if (!lock)
+               return error("unable to lock %s", renamed_ref);
+       lock->force_write = 1;
+       if (write_ref_sha1(lock, orig_sha1, logmsg))
+               return error("unable to save current sha1 in %s", renamed_ref);
+
+       if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
+               return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
+                       oldref, strerror(errno));
+
+       if (delete_ref(oldref, orig_sha1)) {
+               error("unable to delete old %s", oldref);
+               goto rollback;
+       }
+
+       if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) {
+               if (errno==EISDIR) {
+                       if (remove_empty_directories(git_path("%s", newref))) {
+                               error("Directory not empty: %s", newref);
+                               goto rollback;
+                       }
+               } else {
+                       error("unable to delete existing %s", newref);
+                       goto rollback;
+               }
+       }
+
+       if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
+               error("unable to create directory for %s", newref);
+               goto rollback;
+       }
+
+ retry:
+       if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
+               if (errno==EISDIR || errno==ENOTDIR) {
+                       /*
+                        * rename(a, b) when b is an existing
+                        * directory ought to result in ISDIR, but
+                        * Solaris 5.8 gives ENOTDIR.  Sheesh.
+                        */
+                       if (remove_empty_directories(git_path("logs/%s", newref))) {
+                               error("Directory not empty: logs/%s", newref);
+                               goto rollback;
+                       }
+                       goto retry;
+               } else {
+                       error("unable to move logfile tmp-renamed-log to logs/%s: %s",
+                               newref, strerror(errno));
+                       goto rollback;
+               }
+       }
+       logmoved = log;
+
+       lock = lock_ref_sha1_basic(newref, NULL, NULL);
+       if (!lock) {
+               error("unable to lock %s for update", newref);
+               goto rollback;
+       }
+
+       lock->force_write = 1;
+       hashcpy(lock->old_sha1, orig_sha1);
+       if (write_ref_sha1(lock, orig_sha1, logmsg)) {
+               error("unable to write current sha1 into %s", newref);
+               goto rollback;
+       }
+
+       if (!strncmp(oldref, "refs/heads/", 11) &&
+                       !strncmp(newref, "refs/heads/", 11)) {
+               char oldsection[1024], newsection[1024];
+
+               snprintf(oldsection, 1024, "branch.%s", oldref + 11);
+               snprintf(newsection, 1024, "branch.%s", newref + 11);
+               if (git_config_rename_section(oldsection, newsection) < 0)
+                       return 1;
+       }
+
+       return 0;
+
+ rollback:
+       lock = lock_ref_sha1_basic(oldref, NULL, NULL);
+       if (!lock) {
+               error("unable to lock %s for rollback", oldref);
+               goto rollbacklog;
+       }
+
+       lock->force_write = 1;
+       flag = log_all_ref_updates;
+       log_all_ref_updates = 0;
+       if (write_ref_sha1(lock, orig_sha1, NULL))
+               error("unable to write current sha1 into %s", oldref);
+       log_all_ref_updates = flag;
+
+ rollbacklog:
+       if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
+               error("unable to restore logfile %s from %s: %s",
+                       oldref, newref, strerror(errno));
+       if (!logmoved && log &&
+           rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
+               error("unable to restore logfile %s from tmp-renamed-log: %s",
+                       oldref, strerror(errno));
+
+       return 1;
+}
+
 void unlock_ref(struct ref_lock *lock)
 {
        if (lock->lock_fd >= 0) {
@@ -797,8 +928,12 @@ static int log_ref_write(struct ref_lock *lock,
        char *logrec;
        const char *committer;
 
+       if (log_all_ref_updates < 0)
+               log_all_ref_updates = !is_bare_repository();
+
        if (log_all_ref_updates &&
-           !strncmp(lock->ref_name, "refs/heads/", 11)) {
+           (!strncmp(lock->ref_name, "refs/heads/", 11) ||
+            !strncmp(lock->ref_name, "refs/remotes/", 13))) {
                if (safe_create_leading_directories(lock->log_file) < 0)
                        return error("unable to create directory for %s",
                                lock->log_file);
@@ -841,7 +976,7 @@ static int log_ref_write(struct ref_lock *lock,
                        sha1_to_hex(sha1),
                        committer);
        }
-       written = len <= maxlen ? write(logfd, logrec, len) : -1;
+       written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
        free(logrec);
        close(logfd);
        if (written != len)
@@ -860,8 +995,8 @@ int write_ref_sha1(struct ref_lock *lock,
                unlock_ref(lock);
                return 0;
        }
-       if (write(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
-           write(lock->lock_fd, &term, 1) != 1
+       if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
+           write_in_full(lock->lock_fd, &term, 1) != 1
                || close(lock->lock_fd) < 0) {
                error("Couldn't write %s", lock->lk->filename);
                unlock_ref(lock);
@@ -886,7 +1021,7 @@ int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *
 {
        const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
        char *tz_c;
-       int logfd, tz;
+       int logfd, tz, reccnt = 0;
        struct stat st;
        unsigned long date;
        unsigned char logged_sha1[20];
@@ -898,12 +1033,13 @@ int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *
        fstat(logfd, &st);
        if (!st.st_size)
                die("Log %s is empty.", logfile);
-       logdata = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0);
+       logdata = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0);
        close(logfd);
 
        lastrec = NULL;
        rec = logend = logdata + st.st_size;
        while (logdata < rec) {
+               reccnt++;
                if (logdata < rec && *(rec-1) == '\n')
                        rec--;
                lastgt = NULL;
@@ -960,7 +1096,53 @@ int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *
        if (get_sha1_hex(logdata, sha1))
                die("Log %s is corrupt.", logfile);
        munmap((void*)logdata, st.st_size);
-       fprintf(stderr, "warning: Log %s only goes back to %s.\n",
-               logfile, show_rfc2822_date(date, tz));
+       if (at_time)
+               fprintf(stderr, "warning: Log %s only goes back to %s.\n",
+                       logfile, show_rfc2822_date(date, tz));
+       else
+               fprintf(stderr, "warning: Log %s only has %d entries.\n",
+                       logfile, reccnt);
        return 0;
 }
+
+int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
+{
+       const char *logfile;
+       FILE *logfp;
+       char buf[1024];
+
+       logfile = git_path("logs/%s", ref);
+       logfp = fopen(logfile, "r");
+       if (!logfp)
+               return -1;
+       while (fgets(buf, sizeof(buf), logfp)) {
+               unsigned char osha1[20], nsha1[20];
+               char *email_end, *message;
+               unsigned long timestamp;
+               int len, ret, tz;
+
+               /* old SP new SP name <email> SP time TAB msg LF */
+               len = strlen(buf);
+               if (len < 83 || buf[len-1] != '\n' ||
+                   get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
+                   get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
+                   !(email_end = strchr(buf + 82, '>')) ||
+                   email_end[1] != ' ' ||
+                   !(timestamp = strtoul(email_end + 2, &message, 10)) ||
+                   !message || message[0] != ' ' ||
+                   (message[1] != '+' && message[1] != '-') ||
+                   !isdigit(message[2]) || !isdigit(message[3]) ||
+                   !isdigit(message[4]) || !isdigit(message[5]) ||
+                   message[6] != '\t')
+                       continue; /* corrupt? */
+               email_end[1] = '\0';
+               tz = strtol(message + 1, NULL, 10);
+               message += 7;
+               ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
+               if (ret)
+                       return ret;
+       }
+       fclose(logfp);
+       return 0;
+}
+