Empty file as pointer to tree and built-in compare().

1 files changed, 36 insertions, 52 deletions

diff --git a/vcx b/vcx
index db94101..38d2355 100644
--- a/vcx
+++ b/vcx
@@ -5,6 +5,7 @@ use warnings;
 use File::Path qw(make_path);
 use File::Copy qw(copy);
 use File::Find;
+use File::Compare;
 use File::Basename;
 use File::Glob qw(:bsd_glob);
 use File::Spec;
@@ -12,18 +13,15 @@ use Digest::SHA qw(sha1_hex);
 use POSIX qw(strftime);
 
 use constant VCX_DIR	=> '.vcx';
+use constant HEAD       => VCX_DIR . '/head';	# Current commit ID
 use constant OBJ_DIR	=> VCX_DIR . '/objs';	# Latest version of a file
 use constant REV_DIR	=> VCX_DIR . '/revs';	# Commits
-use constant TREE_DIR	=> VCX_DIR . '/trees';	# Trees
-use constant HEAD_FILE  => VCX_DIR . '/head';	# Current commit ID
 
 # Staging area
 use constant TMP_DIR	=> VCX_DIR . '/index';
 use constant TMP_TREE   => TMP_DIR . '/tree';
 use constant TMP_DIFF   => TMP_DIR . '/deltas';
-
-use constant TMP_META_FILE  => VCX_DIR . '/meta';
-use constant TMP_TREE_FILE  => VCX_DIR . '/tree';
+use constant TMP_META_FILE  => TMP_DIR . '/meta';
 
 my $cmd = shift @ARGV // '';
 my @args = @ARGV;
@@ -48,33 +46,32 @@ if ($cmd eq 'init') {
 }
 
 sub run_init {
-	make_path(OBJ_DIR, REV_DIR, TREE_DIR);
+	make_path(OBJ_DIR, REV_DIR);
 
 	my $initial_hex = to_hex_id(0);
 	my $rev0_dir = File::Spec->catfile(REV_DIR, $initial_hex);
 	make_path($rev0_dir);
 
-	write_file(HEAD_FILE, "$initial_hex\n");
+	write_file(HEAD, "$initial_hex\n");
 
 	# Baseline tree (empty)
 	my $empty_tree_hash = sha1_hex(""); 
-	write_file(File::Spec->catfile($rev0_dir, "tree"), "$empty_tree_hash\n");
-	make_path(File::Spec->catdir(TREE_DIR, $empty_tree_hash));
+	my $empty_tree_file = File::Spec->catfile($rev0_dir, "tree-$empty_tree_hash");
+	open my $fh, '>', $empty_tree_file or die $!; close $fh;
+	make_path(File::Spec->catdir(OBJ_DIR, $empty_tree_hash));
 
 	open my $mfh, '>', File::Spec->catfile($rev0_dir, "message"); close $mfh;
-
 	print "Initialized repository.\n";
 }
 
 sub run_status {
-	open my $fh, '<', HEAD_FILE or die "VCX not initialized.\n";
+	open my $fh, '<', HEAD or die "VCX not initialized.\n";
 	my $head = <$fh>; chomp $head; close $fh;
 	print "On revision [$head]\n";
 
-	my $tree_hash_path = File::Spec->catfile(REV_DIR, $head, "tree");
-	open my $tp_fh, '<', $tree_hash_path or die $!;
-	my $tree_hash = <$tp_fh>; chomp $tree_hash; close $tp_fh;
-	my $latest_tree_dir = File::Spec->catdir(TREE_DIR, $tree_hash);
+	my ($tree_ptr) = bsd_glob(File::Spec->catfile(REV_DIR, $head, "tree-*"));
+	my ($tree_hash) = $tree_ptr =~ /tree-([a-f0-9]{40})$/;
+	my $latest_tree_dir = File::Spec->catdir(OBJ_DIR, $tree_hash);
 
 	# Pass 1: Workspace -> History (Detects New and Modified)
 	find({
@@ -89,7 +86,7 @@ sub run_status {
 
 			if (-e $base_in_tree || -l $base_in_tree) {
 				my $obj_in_store = readlink($base_in_tree);
-				if (!compare_files($File::Find::name, $obj_in_store)) {
+				if (compare($_, $obj_in_store) != 0) {
 					my $staged = check_staged_status($rel, 'M') ? " (staged)" : "";
 					print "[M] $rel$staged\n";
 				}
@@ -147,15 +144,15 @@ sub check_staged_status {
 
 sub run_add {
 	my @targets = @_;
-	make_path(TMP_TREE, TMP_DIFF);
 
-	open my $fh_h, '<', HEAD_FILE or die $!;
+	make_path(TMP_TREE);
+
+	open my $fh_h, '<', HEAD or die $!;
 	my $head = <$fh_h>; chomp $head; close $fh_h;
 
-	my $latest_tree_hash_path = File::Spec->catfile(REV_DIR, $head, "tree");
-	open my $tp_fh, '<', $latest_tree_hash_path or die $!;
-	my $latest_tree_hash = <$tp_fh>; chomp $latest_tree_hash; close $tp_fh;
-	my $latest_tree_dir = File::Spec->catdir(TREE_DIR, $latest_tree_hash);
+	my ($latest_tree_ptr) = bsd_glob(File::Spec->catfile(REV_DIR, $head, "tree-*"));
+	my ($latest_tree_hash) = $latest_tree_ptr =~ /tree-([a-f0-9]{40})$/;
+	my $latest_tree_dir = File::Spec->catdir(OBJ_DIR, $latest_tree_hash);
 
 	my $next_id_hex = to_hex_id(from_hex_id($head) + 1);
 
@@ -183,12 +180,12 @@ sub run_add {
 					my $prev_link = File::Spec->catfile($latest_tree_dir, $rel);
 
 					# CASE 1: Regular File
-					if (-f $File::Find::name && !-l $File::Find::name) {
+					if (-f $_ && !-l _) {
 						return if -e $staged_path; # Already staged
 
 						if (-l $prev_link) {
 							my $obj_in_head = readlink($prev_link);
-							return if compare_files($File::Find::name, $obj_in_head);
+							return if compare($_, $obj_in_head) == 0;
 						}
 
 						# Generate deltas if modified
@@ -198,8 +195,10 @@ sub run_add {
 						if (-e $obj_path) {
 							my $p_path = File::Spec->catfile(TMP_DIFF, "$obj_name.$next_id_hex.patch");
 							if (-T $_) {
-								system("diff -u '$obj_path' '$_' > '$p_path'") 
-									if system("diff -q '$obj_path' '$_' > /dev/null") != 0;
+								if (compare($_, $obj_path) != 0) {
+									unless (-d TMP_DIFF) { make_path(TMP_DIFF); }
+									system("diff -u '$obj_path' '$_' > '$p_path'");
+								}
 							} else {
 								make_bin_patch($_, $obj_path, $p_path);
 							}
@@ -232,16 +231,18 @@ sub run_add {
 
 	my $tree_data = join("\n", sort @entries);
 	my $tree_hash = sha1_hex($tree_data);
-	write_file(TMP_TREE_FILE, $tree_hash);
+	my $tree_file = File::Spec->catfile(TMP_DIR, "tree-$tree_hash");
+	open my $fh, '>', $tree_file or die $!; close $fh;
 }
 
 sub run_commit {
 	my ($message) = @_;
 
 	my $content_changed = -s TMP_META_FILE;
-	open my $th_fh, '<', TMP_TREE_FILE or die $!;
-	my $staged_hash = <$th_fh>; chomp $staged_hash; close $th_fh;
-	my $tree_path = File::Spec->catdir(TREE_DIR, $staged_hash);
+
+	my ($staged_tree_ptr) = bsd_glob(File::Spec->catfile(TMP_DIR, "tree-*"));
+	my ($tree_hash) = $staged_tree_ptr =~ /tree-([a-f0-9]{40})$/;
+	my $tree_path = File::Spec->catdir(OBJ_DIR, $tree_hash);
 	my $tree_exists = -d $tree_path;
 
 	if ($tree_exists && !$content_changed) {
@@ -256,7 +257,7 @@ sub run_commit {
 	}
 
 	# Prepare IDs
-	open my $fh_h, '<', HEAD_FILE or die "Not a repository.\n";
+	open my $fh_h, '<', HEAD or die "Not a repository.\n";
 	my $old_head = <$fh_h>; chomp $old_head; close $fh_h;
 	my $next_id_hex = to_hex_id(from_hex_id($old_head) + 1);
 	my $rev_dir = File::Spec->catfile(REV_DIR, $next_id_hex);
@@ -280,7 +281,7 @@ sub run_commit {
 		rename(TMP_TREE, $tree_path) or die "Failed to save directories: $!";
 	}
 
-	rename(TMP_TREE_FILE, File::Spec->catfile($rev_dir, "tree")) 
+	rename($staged_tree_ptr, File::Spec->catfile($rev_dir, "tree-$tree_hash")) 
 		or die "Failed to save tree pointer to revision: $!";	
 
 	# Move deltas
@@ -291,7 +292,7 @@ sub run_commit {
 	}
 
 	write_file(File::Spec->catfile($rev_dir, "message"), "$message\n");
-	write_file(HEAD_FILE, "$next_id_hex\n"); # Update head
+	write_file(HEAD, "$next_id_hex\n"); # Update head
 
 	File::Path::remove_tree(TMP_DIR) if -d TMP_DIR;
 	
@@ -300,7 +301,7 @@ sub run_commit {
 }
 
 sub run_log {
-	open my $fh_h, '<', HEAD_FILE or die "Not a repository.\n";
+	open my $fh_h, '<', HEAD or die "Not a repository.\n";
 	my $head = <$fh_h>; chomp $head; close $fh_h;
 
 	# Setup pager
@@ -370,7 +371,7 @@ sub stage_link {
 sub stage_deletions {
 	my ($target) = @_; 
 	 
-	open my $fh, '<', HEAD_FILE or die "Not a repository.\n";
+	open my $fh, '<', HEAD or die "Not a repository.\n";
 	my $head = <$fh>; chomp $head; close $fh;
 	my $latest_tree  = File::Spec->catfile(REV_DIR, $head, "tree");
 
@@ -457,23 +458,6 @@ sub apply_bin_patch {
 	close $ptch_fh;
 }
 
-sub compare_files {
-	my ($file1, $file2) = @_;
-	return 0 unless -s $file1 == -s $file2;
-
-	open my $fh1, '<:raw', $file1 or return 0;
-	open my $fh2, '<:raw', $file2 or return 0;
-
-	my $blk_size = 4096;
-	while (1) {
-		my $read1 = sysread($fh1, my $buf1, $blk_size);
-		my $read2 = sysread($fh2, my $buf2, $blk_size);
-		return 0 if $buf1 ne $buf2;
-		last if $read1 == 0;
-	}
-	return 1;
-}
-
 # Convert decimal to a padded 7-char hex string
 sub to_hex_id { sprintf("%07x", $_[0]) }