What are patches? Applying Patches Creating Patches
Note
This is pretty hard to explain to a beginner. Contributions are welcome. What are patches?
A patch is a set of instructions that tell you (or a program) what changes to make to add a feature to your gallery. The advantage of a patch over just getting the whole files, is that a patch can make the changes to files that have already have changes to them. If you copied files over, you'd lose the other changes.
Patches can be of three different forms "normal", context, and unified (and unified-context). Here's what each looks like.
Let's say this is the original file:
1 The rain
2 On the plain
3 -Says Alice
4
5 Let's keep this sentence.
6 Let's ditch this long
7 and boring sentence.
And the changed file...
1 The rain
2 In Spain
3 Falls mainly
4 On the plain
5 -Says Bob
6 7 Let's keep this sentence.
Normal
///we'll Append these after line 1 to become lines 2--3///
1a2,3
> In Spain
> Falls mainly
///we'll Change line 3, which in the new file is line 5///
3c5
< -Says Alice
---
> -Says Bob
///we'll Delete lines 6--7, but they would've been at line 7 in the new file///
6,7d7
< Let's ditch this long
< and boring sentence.
Context
*** file.orig Sat Jan 01 00:00:00 2000 ///the original filename///
--- file Tue Apr 29 00:00:00 2003
///the start of a "hunk" of text to change///
***************
///start/end line numbers in your original file///
*** 1,8 ****
///lines with no "!", "-", or "+" are there for context///
The rain
On the plain
///the "!' means this line will have a change (see below)///
! -Says Alice
Let's keep this sentence.
///the "-" means this line should be deleted///
- Let's ditch this long
- and boring sentence.
///start/end line numbers in changed file///
--- 1,8 ----
The rain
///the "+" means this line should be added///
+ In Spain
+ Falls Mainly
On the plain
///this is the change for the line marked "!" up above///
! -Says Bob
Let's keep this sentence.
Unified
--- file.orig Sat Jan 01 00:00:00 2000 ///the original filename///
+++ file Tue Apr 29 00:00:00 2003
///the start of a "hunk". "-#,#" gives the lines in the original file,
while "+#,#" gies the lines in the file once it's changed.///
@@ -1,8 +1,8 @@
///again, lines with no "-" or "+" are contextual///
The rain
+In Spain
+Falls Mainly
On the plain
///the "replace" is made by a line delete followed by a line add///
--Says Alice
+-Says Bob
Let's keep this sentence.
-Let's ditch this long
-and boring sentence.
Applying Patches
Applying patches is easiest with ssh or telnet access. Basically, just copy the patch to the directory you'd like to patch. Then simply type patch -p0 < patchfile.txt
If you're using Windows, you need the patch.exe program from http://unxutils.sourceforge.net/. Then simply using this command: patch -p0 -i patchfile.txt.
If only have FTP access, you'll have to apply the patchfile manually. Add lines with +, delete lines with -, and change lines with !. It's painful, but you will get the hang of it. Warning
Always back up your Gallery before patching it. Note
If the patch was made with a different version of Gallery than you're using, it probably won't work. You may need to apply at least part of the patch manually. Creating Patches Warning
Before making a patch, especially to distribute to the public, make sure you have throughly tested it! If possible, build patches aganist the latest stable version and CVS version. Creating Patches with CVS
For more information about using CVS see: http://www.cvshome.org. For more information about how to check Gallery out via CVS, see http://sourceforge.net/cvs/?group_id=7130.
Once you have created the patch, simply type this command: cvs diff -cu > patch.txt. patch.txt will now contain the patch.
Then build a zip file containing this patch and any new files that you have created as part of this change. Upload them somewhere on the web, and publish the link.
It's just as easy to make patches under Windows as it is under *nix. You just need the correct tools installed. See the GNUWin32 Project for the "diffutils-bin" package and it's requirements. Also get "patch-bin" as well.
