t1007: annotate with SHA1 prerequisite
[gitweb.git] / archive-tar.c
index cb99df28142f164da62f5a728eb9019e57804157..3563bcb9f263f7782a77c679bf9be32af6bd13df 100644 (file)
@@ -2,6 +2,7 @@
  * Copyright (c) 2005, 2006 Rene Scharfe
  */
 #include "cache.h"
+#include "config.h"
 #include "tar.h"
 #include "archive.h"
 #include "streaming.h"
@@ -18,6 +19,24 @@ static int tar_umask = 002;
 static int write_tar_filter_archive(const struct archiver *ar,
                                    struct archiver_args *args);
 
+/*
+ * This is the max value that a ustar size header can specify, as it is fixed
+ * at 11 octal digits. POSIX specifies that we switch to extended headers at
+ * this size.
+ *
+ * Likewise for the mtime (which happens to use a buffer of the same size).
+ */
+#if ULONG_MAX == 0xFFFFFFFF
+#define USTAR_MAX_SIZE ULONG_MAX
+#else
+#define USTAR_MAX_SIZE 077777777777UL
+#endif
+#if TIME_MAX == 0xFFFFFFFF
+#define USTAR_MAX_MTIME TIME_MAX
+#else
+#define USTAR_MAX_MTIME 077777777777ULL
+#endif
+
 /* writes out the whole block, but only if it is full */
 static void write_if_needed(void)
 {
@@ -92,7 +111,7 @@ 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)
+static int stream_blocked(const struct object_id *oid)
 {
        struct git_istream *st;
        enum object_type type;
@@ -100,9 +119,9 @@ static int stream_blocked(const unsigned char *sha1)
        char buf[BLOCKSIZE];
        ssize_t readlen;
 
-       st = open_istream(sha1, &type, &sz, NULL);
+       st = open_istream(oid, &type, &sz, NULL);
        if (!st)
-               return error("cannot stream blob %s", sha1_to_hex(sha1));
+               return error("cannot stream blob %s", oid_to_hex(oid));
        for (;;) {
                readlen = read_istream(st, buf, sizeof(buf));
                if (readlen <= 0)
@@ -137,6 +156,20 @@ static void strbuf_append_ext_header(struct strbuf *sb, const char *keyword,
        strbuf_addch(sb, '\n');
 }
 
+/*
+ * Like strbuf_append_ext_header, but for numeric values.
+ */
+static void strbuf_append_ext_header_uint(struct strbuf *sb,
+                                         const char *keyword,
+                                         uintmax_t value)
+{
+       char buf[40]; /* big enough for 2^128 in decimal, plus NUL */
+       int len;
+
+       len = xsnprintf(buf, sizeof(buf), "%"PRIuMAX, value);
+       strbuf_append_ext_header(sb, keyword, buf, len);
+}
+
 static unsigned int ustar_header_chksum(const struct ustar_header *header)
 {
        const unsigned char *p = (const unsigned char *)header;
@@ -184,31 +217,30 @@ static void prepare_header(struct archiver_args *args,
        xsnprintf(header->chksum, sizeof(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)
+static void write_extended_header(struct archiver_args *args,
+                                 const struct object_id *oid,
+                                 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;
-       xsnprintf(header.name, sizeof(header.name), "%s.paxheader", sha1_to_hex(sha1));
+       xsnprintf(header.name, sizeof(header.name), "%s.paxheader", oid_to_hex(oid));
        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 struct object_id *oid,
                           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;
+       unsigned long size, size_in_header;
        void *buffer;
        int err = 0;
 
@@ -225,7 +257,7 @@ static int write_tar_entry(struct archiver_args *args,
                mode = (mode | ((mode & 0100) ? 0777 : 0666)) & ~tar_umask;
        } else {
                return error("unsupported file mode: 0%o (SHA1: %s)",
-                            mode, sha1_to_hex(sha1));
+                            mode, oid_to_hex(oid));
        }
        if (pathlen > sizeof(header.name)) {
                size_t plen = get_path_prefix(path, pathlen,
@@ -236,7 +268,7 @@ static int write_tar_entry(struct archiver_args *args,
                        memcpy(header.name, path + plen + 1, rest);
                } else {
                        xsnprintf(header.name, sizeof(header.name), "%s.data",
-                                 sha1_to_hex(sha1));
+                                 oid_to_hex(oid));
                        strbuf_append_ext_header(&ext_header, "path",
                                                 path, pathlen);
                }
@@ -244,14 +276,14 @@ static int write_tar_entry(struct archiver_args *args,
                memcpy(header.name, path, pathlen);
 
        if (S_ISREG(mode) && !args->convert &&
-           sha1_object_info(sha1, &size) == OBJ_BLOB &&
+           oid_object_info(oid, &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);
+               buffer = object_file_to_archive(args, path, oid, old_mode, &type, &size);
                if (!buffer)
-                       return error("cannot read %s", sha1_to_hex(sha1));
+                       return error("cannot read %s", oid_to_hex(oid));
        } else {
                buffer = NULL;
                size = 0;
@@ -260,22 +292,24 @@ static int write_tar_entry(struct archiver_args *args,
        if (S_ISLNK(mode)) {
                if (size > sizeof(header.linkname)) {
                        xsnprintf(header.linkname, sizeof(header.linkname),
-                                 "see %s.paxheader", sha1_to_hex(sha1));
+                                 "see %s.paxheader", oid_to_hex(oid));
                        strbuf_append_ext_header(&ext_header, "linkpath",
                                                 buffer, size);
                } else
                        memcpy(header.linkname, buffer, size);
        }
 
-       prepare_header(args, &header, mode, size);
+       size_in_header = size;
+       if (S_ISREG(mode) && size > USTAR_MAX_SIZE) {
+               size_in_header = 0;
+               strbuf_append_ext_header_uint(&ext_header, "size", size);
+       }
+
+       prepare_header(args, &header, mode, size_in_header);
 
        if (ext_header.len > 0) {
-               err = write_extended_header(args, sha1, ext_header.buf,
-                                           ext_header.len);
-               if (err) {
-                       free(buffer);
-                       return err;
-               }
+               write_extended_header(args, oid, ext_header.buf,
+                                     ext_header.len);
        }
        strbuf_release(&ext_header);
        write_blocked(&header, sizeof(header));
@@ -283,21 +317,31 @@ static int write_tar_entry(struct archiver_args *args,
                if (buffer)
                        write_blocked(buffer, size);
                else
-                       err = stream_blocked(sha1);
+                       err = stream_blocked(oid);
        }
        free(buffer);
        return err;
 }
 
-static int write_global_extended_header(struct archiver_args *args)
+static void write_global_extended_header(struct archiver_args *args)
 {
        const unsigned char *sha1 = args->commit_sha1;
        struct strbuf ext_header = STRBUF_INIT;
        struct ustar_header header;
        unsigned int mode;
-       int err = 0;
 
-       strbuf_append_ext_header(&ext_header, "comment", sha1_to_hex(sha1), 40);
+       if (sha1)
+               strbuf_append_ext_header(&ext_header, "comment",
+                                        sha1_to_hex(sha1), 40);
+       if (args->time > USTAR_MAX_MTIME) {
+               strbuf_append_ext_header_uint(&ext_header, "mtime",
+                                             args->time);
+               args->time = USTAR_MAX_MTIME;
+       }
+
+       if (!ext_header.len)
+               return;
+
        memset(&header, 0, sizeof(header));
        *header.typeflag = TYPEFLAG_GLOBAL_HEADER;
        mode = 0100666;
@@ -306,7 +350,6 @@ static int write_global_extended_header(struct archiver_args *args)
        write_blocked(&header, sizeof(header));
        write_blocked(ext_header.buf, ext_header.len);
        strbuf_release(&ext_header);
-       return err;
 }
 
 static struct archiver **tar_filters;
@@ -382,10 +425,8 @@ static int write_tar_archive(const struct archiver *ar,
 {
        int err = 0;
 
-       if (args->commit_sha1)
-               err = write_global_extended_header(args);
-       if (!err)
-               err = write_archive_entries(args, write_tar_entry);
+       write_global_extended_header(args);
+       err = write_archive_entries(args, write_tar_entry);
        if (!err)
                write_trailer();
        return err;