How to apply patches for application programs?

ganninu · 10-21-2003, 04:42 PM

I think this is a question many newbies like me ask. A lot of times I checkout software on sourceforge which has a section called "patches" but I have never had the opportunity to discover what is a patch excatly, and how to apply it? Lately I came across XCHAT2 which has patches which ar every recommended to install (for security reasons). The patches are in .diff format... Can someone illuminate this argument? Thanks. Ganninu.

unSpawn · 10-22-2003, 08:05 AM

//moderator.note: moved to Linux - General, because it isn't about security, but the process of patching. A patch is the output from diff ("diff -Naur oldfile newfile > oldfile.diff"), and to use it you could "cat patch.diff | patch --dry-run -p 1 -b /dir/with/xchat2/sourcecode". The "p 1" strips one directory level in the patch before applying, "-b" makes backups, and using "--dry-run" it won't apply the patch but test if it will work. Note any messages about rejects, because you're supposed to patch those parts manually. If satisfied it will work OK, remove the "--dry-run" switch and let it rip.

ganninu · 10-22-2003, 08:20 AM

I don't understand why one has to strip one directory level in the patch though...

ganninu · 10-22-2003, 01:04 PM

Ok got it... thanks a lot... I understood the -p1 concept. I applied all the patches except one... It made reference to more than one source file:

# fixes 64bit issues (where a pointer to int was given, instead of gsize).
--- xchat-2.0.5/src/common/server.c 2003-08-11 01:40:15.000000000 +1000
+++ xchat-2.0.6/src/common/server.c 2003-10-07 14:54:26.000000000 +1000
@@ -289,8 +289,8 @@
{
char *conv_line; /* holds a copy of the original string */
int conv_len; /* tells g_convert how much of line to convert */
- int utf_len;
- int read_len;
+ gsize utf_len;
+ gsize read_len;
GError *err;
gboolean retry;

--- xchat-2.0.5/src/common/text.c 2003-09-21 20:36:15.000000000 +1000
+++ xchat-2.0.6/src/common/text.c 2003-10-07 15:01:06.000000000 +1000
@@ -446,7 +446,7 @@
get_stamp_str (char *fmt, time_t tim, char **ret)
{
char dest[128];
- int len;
+ gsize len;

len = strftime (dest, sizeof (dest), fmt, localtime (&tim));
if (len)
--- xchat-2.0.5/src/fe-gtk/xtext.c 2003-09-18 15:26:52.000000000 +1000
+++ xchat-2.0.6/src/fe-gtk/xtext.c 2003-10-07 14:57:14.000000000 +1000
@@ -2126,6 +2126,7 @@
char *stripped;
guchar *new_text;
int len;
+ gsize glen;

stripped = gtk_xtext_selection_get_text (xtext, &len);
if (!stripped)
@@ -2158,9 +2159,9 @@
}
break;
default:
- new_text = g_locale_from_utf8 (stripped, len, NULL, &len, NULL);
+ new_text = g_locale_from_utf8 (stripped, len, NULL, &glen, NULL);
gtk_selection_data_set (selection_data_ptr, GDK_SELECTION_TYPE_STRING,
- 8, new_text, len);
+ 8, new_text, glen);
g_free (new_text);
}

How can I patch the source code then? I tried entering all the filenames after the patch command but it doesn't seem to accept more than 1 filename... Or should I edit the patch myself to split it in several diff files?