for_each_reflog_ent(): extract a helper to process a single entry
[gitweb.git] / archive-tar.c
index 20af0051a334a1357b055ea10d74f5380117ab68..0ba3f25cf579d6629566a39d4d5ac19b51293ed5 100644 (file)
@@ -4,6 +4,7 @@
 #include "cache.h"
 #include "tar.h"
 #include "archive.h"
+#include "streaming.h"
 #include "run-command.h"
 
 #define RECORDSIZE     (512)
@@ -30,10 +31,9 @@ static void write_if_needed(void)
  * queues up writes, so that all our write(2) calls write exactly one
  * full block; pads writes to RECORDSIZE
  */
-static void write_blocked(const void *data, unsigned long size)
+static void do_write_blocked(const void *data, unsigned long size)
 {
        const char *buf = data;
-       unsigned long tail;
 
        if (offset) {
                unsigned long chunk = BLOCKSIZE - offset;
@@ -54,6 +54,11 @@ static void write_blocked(const void *data, unsigned long size)
                memcpy(block + offset, buf, size);
                offset += size;
        }
+}
+
+static void finish_record(void)
+{
+       unsigned long tail;
        tail = offset % RECORDSIZE;
        if (tail)  {
                memset(block + offset, 0, RECORDSIZE - tail);
@@ -62,6 +67,12 @@ static void write_blocked(const void *data, unsigned long size)
        write_if_needed();
 }
 
+static void write_blocked(const void *data, unsigned long size)
+{
+       do_write_blocked(data, size);
+       finish_record();
+}
+
 /*
  * The end of tar archives is marked by 2*512 nul bytes and after that
  * follows the rest of the block (if any).
@@ -77,6 +88,33 @@ static void write_trailer(void)
        }
 }
 
+/*
+ * queues up writes, so that all our write(2) calls write exactly one
+ * full block; pads writes to RECORDSIZE
+ */
+static int stream_blocked(const unsigned char *sha1)
+{
+       struct git_istream *st;
+       enum object_type type;
+       unsigned long sz;
+       char buf[BLOCKSIZE];
+       ssize_t readlen;
+
+       st = open_istream(sha1, &type, &sz, NULL);
+       if (!st)
+               return error("cannot stream blob %s", sha1_to_hex(sha1));
+       for (;;) {
+               readlen = read_istream(st, buf, sizeof(buf));
+               if (readlen <= 0)
+                       break;
+               do_write_blocked(buf, readlen);
+       }
+       close_istream(st);
+       if (!readlen)
+               finish_record();
+       return readlen;
+}
+
 /*
  * pax extended header records have the format "%u %s=%s\n".  %u contains
  * the size of the whole string (including the %u), the first %s is the
@@ -101,13 +139,13 @@ static void strbuf_append_ext_header(struct strbuf *sb, const char *keyword,
 
 static unsigned int ustar_header_chksum(const struct ustar_header *header)
 {
-       char *p = (char *)header;
+       const unsigned char *p = (const unsigned char *)header;
        unsigned int chksum = 0;
-       while (p < header->chksum)
+       while (p < (const unsigned char *)header->chksum)
                chksum += *p++;
        chksum += sizeof(header->chksum) * ' ';
        p += sizeof(header->chksum);
-       while (p < (char *)header + sizeof(struct ustar_header))
+       while (p < (const unsigned char *)header + sizeof(struct ustar_header))
                chksum += *p++;
        return chksum;
 }
@@ -123,56 +161,101 @@ static size_t get_path_prefix(const char *path, size_t pathlen, size_t maxlen)
        return i;
 }
 
+static void prepare_header(struct archiver_args *args,
+                          struct ustar_header *header,
+                          unsigned int mode, unsigned long size)
+{
+       sprintf(header->mode, "%07o", mode & 07777);
+       sprintf(header->size, "%011lo", S_ISREG(mode) ? size : 0);
+       sprintf(header->mtime, "%011lo", (unsigned long) args->time);
+
+       sprintf(header->uid, "%07o", 0);
+       sprintf(header->gid, "%07o", 0);
+       strlcpy(header->uname, "root", sizeof(header->uname));
+       strlcpy(header->gname, "root", sizeof(header->gname));
+       sprintf(header->devmajor, "%07o", 0);
+       sprintf(header->devminor, "%07o", 0);
+
+       memcpy(header->magic, "ustar", 6);
+       memcpy(header->version, "00", 2);
+
+       sprintf(header->chksum, "%07o", ustar_header_chksum(header));
+}
+
+static int write_extended_header(struct archiver_args *args,
+                                const unsigned char *sha1,
+                                const void *buffer, unsigned long size)
+{
+       struct ustar_header header;
+       unsigned int mode;
+       memset(&header, 0, sizeof(header));
+       *header.typeflag = TYPEFLAG_EXT_HEADER;
+       mode = 0100666;
+       sprintf(header.name, "%s.paxheader", sha1_to_hex(sha1));
+       prepare_header(args, &header, mode, size);
+       write_blocked(&header, sizeof(header));
+       write_blocked(buffer, size);
+       return 0;
+}
+
 static int write_tar_entry(struct archiver_args *args,
-               const unsigned char *sha1, const char *path, size_t pathlen,
-               unsigned int mode, void *buffer, unsigned long size)
+                          const unsigned char *sha1,
+                          const char *path, size_t pathlen,
+                          unsigned int mode)
 {
        struct ustar_header header;
        struct strbuf ext_header = STRBUF_INIT;
+       unsigned int old_mode = mode;
+       unsigned long size;
+       void *buffer;
        int err = 0;
 
        memset(&header, 0, sizeof(header));
 
-       if (!sha1) {
-               *header.typeflag = TYPEFLAG_GLOBAL_HEADER;
-               mode = 0100666;
-               strcpy(header.name, "pax_global_header");
-       } else if (!path) {
-               *header.typeflag = TYPEFLAG_EXT_HEADER;
-               mode = 0100666;
-               sprintf(header.name, "%s.paxheader", sha1_to_hex(sha1));
+       if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
+               *header.typeflag = TYPEFLAG_DIR;
+               mode = (mode | 0777) & ~tar_umask;
+       } else if (S_ISLNK(mode)) {
+               *header.typeflag = TYPEFLAG_LNK;
+               mode |= 0777;
+       } else if (S_ISREG(mode)) {
+               *header.typeflag = TYPEFLAG_REG;
+               mode = (mode | ((mode & 0100) ? 0777 : 0666)) & ~tar_umask;
        } else {
-               if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
-                       *header.typeflag = TYPEFLAG_DIR;
-                       mode = (mode | 0777) & ~tar_umask;
-               } else if (S_ISLNK(mode)) {
-                       *header.typeflag = TYPEFLAG_LNK;
-                       mode |= 0777;
-               } else if (S_ISREG(mode)) {
-                       *header.typeflag = TYPEFLAG_REG;
-                       mode = (mode | ((mode & 0100) ? 0777 : 0666)) & ~tar_umask;
+               return error("unsupported file mode: 0%o (SHA1: %s)",
+                            mode, sha1_to_hex(sha1));
+       }
+       if (pathlen > sizeof(header.name)) {
+               size_t plen = get_path_prefix(path, pathlen,
+                                             sizeof(header.prefix));
+               size_t rest = pathlen - plen - 1;
+               if (plen > 0 && rest <= sizeof(header.name)) {
+                       memcpy(header.prefix, path, plen);
+                               memcpy(header.name, path + plen + 1, rest);
                } else {
-                       return error("unsupported file mode: 0%o (SHA1: %s)",
-                                       mode, sha1_to_hex(sha1));
+                       sprintf(header.name, "%s.data",
+                               sha1_to_hex(sha1));
+                       strbuf_append_ext_header(&ext_header, "path",
+                                                path, pathlen);
                }
-               if (pathlen > sizeof(header.name)) {
-                       size_t plen = get_path_prefix(path, pathlen,
-                                       sizeof(header.prefix));
-                       size_t rest = pathlen - plen - 1;
-                       if (plen > 0 && rest <= sizeof(header.name)) {
-                               memcpy(header.prefix, path, plen);
-                               memcpy(header.name, path + plen + 1, rest);
-                       } else {
-                               sprintf(header.name, "%s.data",
-                                       sha1_to_hex(sha1));
-                               strbuf_append_ext_header(&ext_header, "path",
-                                               path, pathlen);
-                       }
-               } else
-                       memcpy(header.name, path, pathlen);
+       } else
+               memcpy(header.name, path, pathlen);
+
+       if (S_ISREG(mode) && !args->convert &&
+           sha1_object_info(sha1, &size) == OBJ_BLOB &&
+           size > big_file_threshold)
+               buffer = NULL;
+       else if (S_ISLNK(mode) || S_ISREG(mode)) {
+               enum object_type type;
+               buffer = sha1_file_to_archive(args, path, sha1, old_mode, &type, &size);
+               if (!buffer)
+                       return error("cannot read %s", sha1_to_hex(sha1));
+       } else {
+               buffer = NULL;
+               size = 0;
        }
 
-       if (S_ISLNK(mode) && buffer) {
+       if (S_ISLNK(mode)) {
                if (size > sizeof(header.linkname)) {
                        sprintf(header.linkname, "see %s.paxheader",
                                sha1_to_hex(sha1));
@@ -182,32 +265,25 @@ static int write_tar_entry(struct archiver_args *args,
                        memcpy(header.linkname, buffer, size);
        }
 
-       sprintf(header.mode, "%07o", mode & 07777);
-       sprintf(header.size, "%011lo", S_ISREG(mode) ? size : 0);
-       sprintf(header.mtime, "%011lo", (unsigned long) args->time);
-
-       sprintf(header.uid, "%07o", 0);
-       sprintf(header.gid, "%07o", 0);
-       strlcpy(header.uname, "root", sizeof(header.uname));
-       strlcpy(header.gname, "root", sizeof(header.gname));
-       sprintf(header.devmajor, "%07o", 0);
-       sprintf(header.devminor, "%07o", 0);
-
-       memcpy(header.magic, "ustar", 6);
-       memcpy(header.version, "00", 2);
-
-       sprintf(header.chksum, "%07o", ustar_header_chksum(&header));
+       prepare_header(args, &header, mode, size);
 
        if (ext_header.len > 0) {
-               err = write_tar_entry(args, sha1, NULL, 0, 0, ext_header.buf,
-                               ext_header.len);
-               if (err)
+               err = write_extended_header(args, sha1, ext_header.buf,
+                                           ext_header.len);
+               if (err) {
+                       free(buffer);
                        return err;
+               }
        }
        strbuf_release(&ext_header);
        write_blocked(&header, sizeof(header));
-       if (S_ISREG(mode) && buffer && size > 0)
-               write_blocked(buffer, size);
+       if (S_ISREG(mode) && size > 0) {
+               if (buffer)
+                       write_blocked(buffer, size);
+               else
+                       err = stream_blocked(sha1);
+       }
+       free(buffer);
        return err;
 }
 
@@ -215,11 +291,18 @@ static int write_global_extended_header(struct archiver_args *args)
 {
        const unsigned char *sha1 = args->commit_sha1;
        struct strbuf ext_header = STRBUF_INIT;
-       int err;
+       struct ustar_header header;
+       unsigned int mode;
+       int err = 0;
 
        strbuf_append_ext_header(&ext_header, "comment", sha1_to_hex(sha1), 40);
-       err = write_tar_entry(args, NULL, NULL, 0, 0, ext_header.buf,
-                       ext_header.len);
+       memset(&header, 0, sizeof(header));
+       *header.typeflag = TYPEFLAG_GLOBAL_HEADER;
+       mode = 0100666;
+       strcpy(header.name, "pax_global_header");
+       prepare_header(args, &header, mode, ext_header.len);
+       write_blocked(&header, sizeof(header));
+       write_blocked(ext_header.buf, ext_header.len);
        strbuf_release(&ext_header);
        return err;
 }