libext2fs: add support for the SOURCE_DATE_EPOCH environment variable

Add SOURCE_DATE_EPOCH support as documented in [1].

[1] https://reproducible-builds.org/specs/source-date-epoch

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/lib/ext2fs/bb_inode.c b/lib/ext2fs/bb_inode.c
index 927a4d4..8b29e1c 100644 (file)
--- a/lib/ext2fs/bb_inode.c
+++ b/lib/ext2fs/bb_inode.c
@@ -20,7 +20,6 @@
 #include <unistd.h>
 #endif
 #include <fcntl.h>
-#include <time.h>
 #if HAVE_SYS_STAT_H
 #include <sys/stat.h>
 #endif
@@ -29,7 +28,7 @@
 #endif
 
 #include "ext2_fs.h"
-#include "ext2fs.h"
+#include "ext2fsP.h"
 
 struct set_badblock_record {
        ext2_badblocks_iterate  bb_iter;
@@ -125,7 +124,7 @@ errcode_t ext2fs_update_bb_inode(ext2_filsys fs, ext2_badblocks_list bb_list)
        if (retval)
                goto cleanup;
 
-       now = fs->now ? fs->now : time(0);
+       now = ext2fsP_get_time(fs);
        ext2fs_inode_xtime_set(&inode, i_atime, now);
        if (!ext2fs_inode_xtime_get(&inode, i_ctime))
                ext2fs_inode_xtime_set(&inode, i_ctime, now);

diff --git a/lib/ext2fs/closefs.c b/lib/ext2fs/closefs.c
index 42bda1f..8e5bec0 100644 (file)
--- a/lib/ext2fs/closefs.c
+++ b/lib/ext2fs/closefs.c
@@ -301,7 +301,7 @@ errcode_t ext2fs_flush2(ext2_filsys fs, int flags)
        fs_state = fs->super->s_state;
        feature_incompat = fs->super->s_feature_incompat;
 
-       ext2fs_set_tstamp(fs->super, s_wtime, fs->now ? fs->now : time(NULL));
+       ext2fs_set_tstamp(fs->super, s_wtime, ext2fsP_get_time(fs));
        fs->super->s_block_group_nr = 0;
 
        /*

diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index f3d98f6..c2638b8 100644 (file)
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -222,6 +222,11 @@ typedef struct ext2_file *ext2_file_t;
 #define EXT2_FLAG_IGNORE_SWAP_DIRENT   0x8000000
 
 /*
+ * Internal flags for use by the ext2fs library only
+ */
+#define EXT2_FLAG2_USE_FAKE_TIME       0x000000001
+
+/*
  * Special flag in the ext2 inode i_flag field that means that this is
  * a new inode.  (So that ext2_write_inode() can clear extra fields.)
  */
@@ -275,10 +280,11 @@ struct struct_ext2_filsys {
        int                             cluster_ratio_bits;
        __u16                           default_bitmap_type;
        __u16                           pad;
+       __u32                           flags2;
        /*
         * Reserved for future expansion
         */
-       __u32                           reserved[5];
+       __u32                           reserved[4];
 
        /*
         * Reserved for the use of the calling application.

diff --git a/lib/ext2fs/ext2fsP.h b/lib/ext2fs/ext2fsP.h
index 0687384..d1f2105 100644 (file)
--- a/lib/ext2fs/ext2fsP.h
+++ b/lib/ext2fs/ext2fsP.h
@@ -26,6 +26,13 @@ static inline int ext2fsP_is_disk_device(mode_t mode)
 #endif
 }
 
+static inline time_t ext2fsP_get_time(ext2_filsys fs)
+{
+       if (fs->now || (fs->flags2 & EXT2_FLAG2_USE_FAKE_TIME))
+               return fs->now;
+       return time(NULL);
+}
+
 /*
  * Badblocks list
  */

diff --git a/lib/ext2fs/ext_attr.c b/lib/ext2fs/ext_attr.c
index 3494046..b33bcce 100644 (file)
--- a/lib/ext2fs/ext_attr.c
+++ b/lib/ext2fs/ext_attr.c
@@ -23,7 +23,7 @@
 #include "ext2_ext_attr.h"
 #include "ext4_acl.h"
 
-#include "ext2fs.h"
+#include "ext2fsP.h"
 
 static errcode_t read_ea_inode_hash(ext2_filsys fs, ext2_ino_t ino, __u32 *hash)
 {
@@ -1342,7 +1342,7 @@ static errcode_t xattr_inode_dec_ref(ext2_filsys fs, ext2_ino_t ino)
                goto write_out;
 
        inode.i_links_count = 0;
-       inode.i_dtime = fs->now ? fs->now : time(0);
+       inode.i_dtime = ext2fsP_get_time(fs);
 
        ret = ext2fs_free_ext_attr(fs, ino, &inode);
        if (ret)

diff --git a/lib/ext2fs/initialize.c b/lib/ext2fs/initialize.c
index 513bf5a..b9cfd1b 100644 (file)
--- a/lib/ext2fs/initialize.c
+++ b/lib/ext2fs/initialize.c
@@ -26,7 +26,7 @@
 #endif
 
 #include "ext2_fs.h"
-#include "ext2fs.h"
+#include "ext2fsP.h"
 
 #ifndef O_BINARY
 #define O_BINARY 0
@@ -125,9 +125,15 @@ errcode_t ext2fs_initialize(const char *name, int flags,
        fs->flags |= EXT2_FLAG_SWAP_BYTES;
 #endif
 
-       time_env = ext2fs_safe_getenv("E2FSPROGS_FAKE_TIME");
-       if (time_env)
+       time_env = ext2fs_safe_getenv("SOURCE_DATE_EPOCH");
+       if (time_env) {
                fs->now = strtoul(time_env, NULL, 0);
+               fs->flags2 |= EXT2_FLAG2_USE_FAKE_TIME;
+       } else {
+               time_env = ext2fs_safe_getenv("E2FSPROGS_FAKE_TIME");
+               if (time_env)
+                       fs->now = strtoul(time_env, NULL, 0);
+       }
 
        io_flags = IO_FLAG_RW;
        if (flags & EXT2_FLAG_EXCLUSIVE)
@@ -218,8 +224,8 @@ errcode_t ext2fs_initialize(const char *name, int flags,
        }
 
        set_field(s_checkinterval, 0);
-       ext2fs_set_tstamp(super, s_mkfs_time, fs->now ? fs->now : time(NULL));
-       ext2fs_set_tstamp(super, s_lastcheck, fs->now ? fs->now : time(NULL));
+       ext2fs_set_tstamp(super, s_mkfs_time, ext2fsP_get_time(fs));
+       ext2fs_set_tstamp(super, s_lastcheck, ext2fsP_get_time(fs));
 
        super->s_creator_os = CREATOR_OS;
 

diff --git a/lib/ext2fs/inode.c b/lib/ext2fs/inode.c
index 8686f99..c9389a2 100644 (file)
--- a/lib/ext2fs/inode.c
+++ b/lib/ext2fs/inode.c
@@ -1042,7 +1042,7 @@ errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino,
        int                     size = EXT2_INODE_SIZE(fs->super);
        struct ext2_inode_large *large_inode;
        errcode_t               retval;
-       time_t                  t = fs->now ? fs->now : time(NULL);
+       time_t                  t = ext2fsP_get_time(fs);
 
        if (!ext2fs_inode_xtime_get(inode, i_atime))
                ext2fs_inode_xtime_set(inode, i_atime, t);

diff --git a/lib/ext2fs/mkjournal.c b/lib/ext2fs/mkjournal.c
index 4a947b6..27cdfa0 100644 (file)
--- a/lib/ext2fs/mkjournal.c
+++ b/lib/ext2fs/mkjournal.c
@@ -20,7 +20,6 @@
 #include <errno.h>
 #endif
 #include <fcntl.h>
-#include <time.h>
 #if HAVE_SYS_STAT_H
 #include <sys/stat.h>
 #endif
@@ -36,7 +35,7 @@
 
 #include "ext2_fs.h"
 #include "e2p/e2p.h"
-#include "ext2fs.h"
+#include "ext2fsP.h"
 
 #include "kernel-jbd.h"
 
@@ -313,7 +312,7 @@ static errcode_t write_journal_inode(ext2_filsys fs, ext2_ino_t journal_ino,
 
        inode_size = (unsigned long long)fs->blocksize *
                        (jparams->num_journal_blocks + jparams->num_fc_blocks);
-       now = fs->now ? fs->now : time(0);
+       now = ext2fsP_get_time(fs);
        ext2fs_inode_xtime_set(&inode, i_mtime, now);
        ext2fs_inode_xtime_set(&inode, i_ctime, now);
        inode.i_links_count = 1;

diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c
index ed2f7c3..2b8e0e7 100644 (file)
--- a/lib/ext2fs/openfs.c
+++ b/lib/ext2fs/openfs.c
@@ -149,9 +149,15 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
        fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
        fs->umask = 022;
 
-       time_env = ext2fs_safe_getenv("E2FSPROGS_FAKE_TIME");
-       if (time_env)
+       time_env = ext2fs_safe_getenv("SOURCE_DATE_EPOCH");
+       if (time_env) {
                fs->now = strtoul(time_env, NULL, 0);
+               fs->flags2 |= EXT2_FLAG2_USE_FAKE_TIME;
+       } else {
+               time_env = ext2fs_safe_getenv("E2FSPROGS_FAKE_TIME");
+               if (time_env)
+                       fs->now = strtoul(time_env, NULL, 0);
+       }
 
        retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
        if (retval)

diff --git a/lib/ext2fs/orphan.c b/lib/ext2fs/orphan.c
index ed89741..913eb9a 100644 (file)
--- a/lib/ext2fs/orphan.c
+++ b/lib/ext2fs/orphan.c
@@ -185,7 +185,7 @@ errcode_t ext2fs_create_orphan_file(ext2_filsys fs, blk_t num_blocks)
        if (err)
                goto out;
        ext2fs_iblk_set(fs, &inode, 0);
-       now = fs->now ? fs->now : time(0);
+       now = ext2fsP_get_time(fs);
        ext2fs_inode_xtime_set(&inode, i_atime, now);
        ext2fs_inode_xtime_set(&inode, i_ctime, now);
        ext2fs_inode_xtime_set(&inode, i_mtime, now);

diff --git a/lib/ext2fs/res_gdt.c b/lib/ext2fs/res_gdt.c
index 8d2a086..3349648 100644 (file)
--- a/lib/ext2fs/res_gdt.c
+++ b/lib/ext2fs/res_gdt.c
@@ -15,7 +15,7 @@
 #include <string.h>
 #include <time.h>
 #include "ext2_fs.h"
-#include "ext2fs.h"
+#include "ext2fsP.h"
 
 /*
  * Iterate through the groups which hold BACKUP superblock/GDT copies in an
@@ -143,7 +143,7 @@ errcode_t ext2fs_create_resize_inode(ext2_filsys fs)
                retval = ext2fs_inode_size_set(fs, &inode, inode_size);
                if (retval)
                        goto out_free;
-               inode.i_ctime = fs->now ? fs->now : time(0);
+               inode.i_ctime = ext2fsP_get_time(fs);
        }
 
        for (rsv_off = 0, gdt_off = fs->desc_blocks,
@@ -235,7 +235,7 @@ out_inode:
               EXT2_I_SIZE(&inode));
 #endif
        if (inode_dirty) {
-               time_t now = fs->now ? fs->now : time(0);
+               time_t now = ext2fsP_get_time(fs);
 
                ext2fs_inode_xtime_set(&inode, i_atime, now);
                ext2fs_inode_xtime_set(&inode, i_mtime, now);