Allow the user to control the verbosity of merge-recursive.
[gitweb.git] / sha1_file.c
index 4d80527baf92a667ca6934406193389ca2c0821d..1b1c0f7b4dc814764ead5ba1af77070ed381110c 100644 (file)
 #endif
 #endif
 
+#ifdef NO_C99_FORMAT
+#define SZ_FMT "lu"
+#else
+#define SZ_FMT "zu"
+#endif
+
 const unsigned char null_sha1[20];
 
 static unsigned int sha1_file_open_flag = O_NOATIME;
@@ -355,10 +361,8 @@ static void read_info_alternates(const char * relative_base, int depth)
                close(fd);
                return;
        }
-       map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+       map = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
        close(fd);
-       if (map == MAP_FAILED)
-               return;
 
        link_alt_odb_entries(map, map + st.st_size, '\n', relative_base, depth);
 
@@ -397,10 +401,36 @@ static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
        return NULL;
 }
 
-static int pack_used_ctr;
-static unsigned long pack_mapped;
+static unsigned int pack_used_ctr;
+static unsigned int pack_mmap_calls;
+static unsigned int peak_pack_open_windows;
+static unsigned int pack_open_windows;
+static size_t peak_pack_mapped;
+static size_t pack_mapped;
+static size_t page_size;
 struct packed_git *packed_git;
 
+void pack_report()
+{
+       fprintf(stderr,
+               "pack_report: getpagesize()            = %10" SZ_FMT "\n"
+               "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n"
+               "pack_report: core.packedGitLimit      = %10" SZ_FMT "\n",
+               page_size,
+               packed_git_window_size,
+               packed_git_limit);
+       fprintf(stderr,
+               "pack_report: pack_used_ctr            = %10u\n"
+               "pack_report: pack_mmap_calls          = %10u\n"
+               "pack_report: pack_open_windows        = %10u / %10u\n"
+               "pack_report: pack_mapped              = "
+                       "%10" SZ_FMT " / %10" SZ_FMT "\n",
+               pack_used_ctr,
+               pack_mmap_calls,
+               pack_open_windows, peak_pack_open_windows,
+               pack_mapped, peak_pack_mapped);
+}
+
 static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
                                void **idx_map_)
 {
@@ -417,10 +447,8 @@ static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
                return -1;
        }
        idx_size = st.st_size;
-       idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
+       idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
        close(fd);
-       if (idx_map == MAP_FAILED)
-               return -1;
 
        index = idx_map;
        *idx_map_ = idx_map;
@@ -450,24 +478,58 @@ static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
        return 0;
 }
 
-static int unuse_one_packed_git(void)
+static void scan_windows(struct packed_git *p,
+       struct packed_git **lru_p,
+       struct pack_window **lru_w,
+       struct pack_window **lru_l)
 {
-       struct packed_git *p, *lru = NULL;
+       struct pack_window *w, *w_l;
 
-       for (p = packed_git; p; p = p->next) {
-               if (!p->windows || p->windows->inuse_cnt)
-                       continue;
-               if (!lru || p->windows->last_used < lru->windows->last_used)
-                       lru = p;
+       for (w_l = NULL, w = p->windows; w; w = w->next) {
+               if (!w->inuse_cnt) {
+                       if (!*lru_w || w->last_used < (*lru_w)->last_used) {
+                               *lru_p = p;
+                               *lru_w = w;
+                               *lru_l = w_l;
+                       }
+               }
+               w_l = w;
        }
-       if (!lru)
-               return 0;
-       munmap(lru->windows->base, lru->windows->len);
-       free(lru->windows);
-       lru->windows = NULL;
-       close(p->pack_fd);
-       p->pack_fd = -1;
-       return 1;
+}
+
+static int unuse_one_window(struct packed_git *current)
+{
+       struct packed_git *p, *lru_p = NULL;
+       struct pack_window *lru_w = NULL, *lru_l = NULL;
+
+       if (current)
+               scan_windows(current, &lru_p, &lru_w, &lru_l);
+       for (p = packed_git; p; p = p->next)
+               scan_windows(p, &lru_p, &lru_w, &lru_l);
+       if (lru_p) {
+               munmap(lru_w->base, lru_w->len);
+               pack_mapped -= lru_w->len;
+               if (lru_l)
+                       lru_l->next = lru_w->next;
+               else {
+                       lru_p->windows = lru_w->next;
+                       if (!lru_p->windows && lru_p != current) {
+                               close(lru_p->pack_fd);
+                               lru_p->pack_fd = -1;
+                       }
+               }
+               free(lru_w);
+               pack_open_windows--;
+               return 1;
+       }
+       return 0;
+}
+
+void release_pack_memory(size_t need)
+{
+       size_t cur = pack_mapped;
+       while (need >= (cur - pack_mapped) && unuse_one_window(NULL))
+               ; /* nothing */
 }
 
 void unuse_pack(struct pack_window **w_cursor)
@@ -485,6 +547,7 @@ static void open_packed_git(struct packed_git *p)
        struct pack_header hdr;
        unsigned char sha1[20];
        unsigned char *idx_sha1;
+       long fd_flag;
 
        p->pack_fd = open(p->pack_name, O_RDONLY);
        if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
@@ -498,8 +561,19 @@ static void open_packed_git(struct packed_git *p)
        } else if (p->pack_size != st.st_size)
                die("packfile %s size changed", p->pack_name);
 
+       /* We leave these file descriptors open with sliding mmap;
+        * there is no point keeping them open across exec(), though.
+        */
+       fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
+       if (fd_flag < 0)
+               die("cannot determine file descriptor flags");
+       fd_flag |= FD_CLOEXEC;
+       if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
+               die("cannot set FD_CLOEXEC");
+
        /* Verify we recognize this pack file format. */
-       read_or_die(p->pack_fd, &hdr, sizeof(hdr));
+       if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
+               die("file %s is far too short to be a packfile", p->pack_name);
        if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
                die("file %s is not a GIT packfile", p->pack_name);
        if (!pack_version_ok(hdr.hdr_version))
@@ -515,37 +589,86 @@ static void open_packed_git(struct packed_git *p)
                        num_packed_objects(p));
        if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
                die("end of packfile %s is unavailable", p->pack_name);
-       read_or_die(p->pack_fd, sha1, sizeof(sha1));
+       if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
+               die("packfile %s signature is unavailable", p->pack_name);
        idx_sha1 = ((unsigned char *)p->index_base) + p->index_size - 40;
        if (hashcmp(sha1, idx_sha1))
                die("packfile %s does not match index", p->pack_name);
 }
 
+static int in_window(struct pack_window *win, unsigned long offset)
+{
+       /* We must promise at least 20 bytes (one hash) after the
+        * offset is available from this window, otherwise the offset
+        * is not actually in this window and a different window (which
+        * has that one hash excess) must be used.  This is to support
+        * the object header and delta base parsing routines below.
+        */
+       off_t win_off = win->offset;
+       return win_off <= offset
+               && (offset + 20) <= (win_off + win->len);
+}
+
 unsigned char* use_pack(struct packed_git *p,
                struct pack_window **w_cursor,
                unsigned long offset,
                unsigned int *left)
 {
-       struct pack_window *win = p->windows;
+       struct pack_window *win = *w_cursor;
 
        if (p->pack_fd == -1)
                open_packed_git(p);
-       if (!win) {
-               pack_mapped += p->pack_size;
-               while (packed_git_limit < pack_mapped && unuse_one_packed_git())
-                       ; /* nothing */
-               win = xcalloc(1, sizeof(*win));
-               win->len = p->pack_size;
-               win->base = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, p->pack_fd, 0);
-               if (win->base == MAP_FAILED)
-                       die("packfile %s cannot be mapped.", p->pack_name);
-               p->windows = win;
+
+       /* Since packfiles end in a hash of their content and its
+        * pointless to ask for an offset into the middle of that
+        * hash, and the in_window function above wouldn't match
+        * don't allow an offset too close to the end of the file.
+        */
+       if (offset > (p->pack_size - 20))
+               die("offset beyond end of packfile (truncated pack?)");
+
+       if (!win || !in_window(win, offset)) {
+               if (win)
+                       win->inuse_cnt--;
+               for (win = p->windows; win; win = win->next) {
+                       if (in_window(win, offset))
+                               break;
+               }
+               if (!win) {
+                       if (!page_size)
+                               page_size = getpagesize();
+                       win = xcalloc(1, sizeof(*win));
+                       win->offset = (offset / page_size) * page_size;
+                       win->len = p->pack_size - win->offset;
+                       if (win->len > packed_git_window_size)
+                               win->len = packed_git_window_size;
+                       pack_mapped += win->len;
+                       while (packed_git_limit < pack_mapped
+                               && unuse_one_window(p))
+                               ; /* nothing */
+                       win->base = xmmap(NULL, win->len,
+                               PROT_READ, MAP_PRIVATE,
+                               p->pack_fd, win->offset);
+                       if (win->base == MAP_FAILED)
+                               die("packfile %s cannot be mapped: %s",
+                                       p->pack_name,
+                                       strerror(errno));
+                       pack_mmap_calls++;
+                       pack_open_windows++;
+                       if (pack_mapped > peak_pack_mapped)
+                               peak_pack_mapped = pack_mapped;
+                       if (pack_open_windows > peak_pack_open_windows)
+                               peak_pack_open_windows = pack_open_windows;
+                       win->next = p->windows;
+                       p->windows = win;
+               }
        }
        if (win != *w_cursor) {
                win->last_used = pack_used_ctr++;
                win->inuse_cnt++;
                *w_cursor = win;
        }
+       offset -= win->offset;
        if (left)
                *left = win->len - offset;
        return win->base + offset;
@@ -721,10 +844,8 @@ void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
                 */
                sha1_file_open_flag = 0;
        }
-       map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+       map = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
        close(fd);
-       if (map == MAP_FAILED)
-               return NULL;
        *size = st.st_size;
        return map;
 }
@@ -903,10 +1024,12 @@ static unsigned long get_delta_base(struct packed_git *p,
        unsigned char *base_info = use_pack(p, w_curs, offset, NULL);
        unsigned long base_offset;
 
-       /* there must be at least 20 bytes left regardless of delta type */
-       if (p->pack_size <= offset + 20)
-               die("truncated pack file");
-
+       /* use_pack() assured us we have [base_info, base_info + 20)
+        * as a range that we can look at without walking off the
+        * end of the mapped window.  Its actually the hash size
+        * that is assured.  An OFS_DELTA longer than the hash size
+        * is stupid, as then a REF_DELTA would be smaller to store.
+        */
        if (kind == OBJ_OFS_DELTA) {
                unsigned used = 0;
                unsigned char c = base_info[used++];
@@ -962,19 +1085,23 @@ static int packed_delta_info(struct packed_git *p,
 
        if (sizep) {
                const unsigned char *data;
-               unsigned char delta_head[20];
+               unsigned char delta_head[20], *in;
                unsigned long result_size;
                z_stream stream;
                int st;
 
                memset(&stream, 0, sizeof(stream));
-
-               stream.next_in = use_pack(p, w_curs, offset, &stream.avail_in);
                stream.next_out = delta_head;
                stream.avail_out = sizeof(delta_head);
 
                inflateInit(&stream);
-               st = inflate(&stream, Z_FINISH);
+               do {
+                       in = use_pack(p, w_curs, offset, &stream.avail_in);
+                       stream.next_in = in;
+                       st = inflate(&stream, Z_FINISH);
+                       offset += stream.next_in - in;
+               } while ((st == Z_OK || st == Z_BUF_ERROR)
+                       && stream.total_out < sizeof(delta_head));
                inflateEnd(&stream);
                if ((st != Z_STREAM_END) &&
                    stream.total_out != sizeof(delta_head))
@@ -1005,6 +1132,12 @@ static unsigned long unpack_object_header(struct packed_git *p,
        unsigned int left;
        unsigned long used;
 
+       /* use_pack() assures us we have [base, base + 20) available
+        * as a range that we can look at at.  (Its actually the hash
+        * size that is assurred.)  With our object header encoding
+        * the maximum deflated object size is 2^137, which is just
+        * insane, so we know won't exceed what we have been given.
+        */
        base = use_pack(p, w_curs, offset, &left);
        used = unpack_object_header_gently(base, left, type, sizep);
        if (!used)
@@ -1103,17 +1236,21 @@ static void *unpack_compressed_entry(struct packed_git *p,
 {
        int st;
        z_stream stream;
-       unsigned char *buffer;
+       unsigned char *buffer, *in;
 
        buffer = xmalloc(size + 1);
        buffer[size] = 0;
        memset(&stream, 0, sizeof(stream));
-       stream.next_in = use_pack(p, w_curs, offset, &stream.avail_in);
        stream.next_out = buffer;
        stream.avail_out = size;
 
        inflateInit(&stream);
-       st = inflate(&stream, Z_FINISH);
+       do {
+               in = use_pack(p, w_curs, offset, &stream.avail_in);
+               stream.next_in = in;
+               st = inflate(&stream, Z_FINISH);
+               offset += stream.next_in - in;
+       } while (st == Z_OK || st == Z_BUF_ERROR);
        inflateEnd(&stream);
        if ((st != Z_STREAM_END) || stream.total_out != size) {
                free(buffer);
@@ -1483,20 +1620,8 @@ int move_temp_to_file(const char *tmpfile, const char *filename)
 
 static int write_buffer(int fd, const void *buf, size_t len)
 {
-       while (len) {
-               ssize_t size;
-
-               size = write(fd, buf, len);
-               if (!size)
-                       return error("file write: disk full");
-               if (size < 0) {
-                       if (errno == EINTR || errno == EAGAIN)
-                               continue;
-                       return error("file write error (%s)", strerror(errno));
-               }
-               len -= size;
-               buf = (char *) buf + size;
-       }
+       if (write_in_full(fd, buf, len) < 0)
+               return error("file write error (%s)", strerror(errno));
        return 0;
 }
 
@@ -1741,7 +1866,7 @@ int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
                        if (ret != Z_OK)
                                break;
                }
-               size = read(fd, buffer + *bufposn, bufsize - *bufposn);
+               size = xread(fd, buffer + *bufposn, bufsize - *bufposn);
                if (size <= 0) {
                        close(local);
                        unlink(tmpfile);
@@ -1864,10 +1989,8 @@ int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, con
 
        buf = "";
        if (size)
-               buf = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
+               buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
        close(fd);
-       if (buf == MAP_FAILED)
-               return -1;
 
        if (!type)
                type = blob_type;