From 8eb867e5f06b6f37b3c6dfaf05e17a14f6edd226 Mon Sep 17 00:00:00 2001
From: Peter Hyman <pete@peterhyman.com>
Date: Sun, 27 Oct 2019 11:17:46 -0500
Subject: [PATCH] fix to allow compression in lrzip.conf to be overridden by
 command line choice.

---
 doc/lrzip.conf.example |  2 +-
 main.c                 | 16 ++++++++++------
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/doc/lrzip.conf.example b/doc/lrzip.conf.example
index 3edee3a..7eaa0d9 100644
--- a/doc/lrzip.conf.example
+++ b/doc/lrzip.conf.example
@@ -13,7 +13,7 @@
 # Use -U setting, Unlimited ram. Yes or No
 # UNLIMITED = NO
 # Compression Method, rzip, gzip, bzip2, lzo, or lzma (default), or zpaq. (-n -g -b -l --lzma -z)
-# If specified here, command line options not usable.
+# May be overriden by command line compression choice.
 # COMPRESSIONMETHOD = lzma
 # Perform LZO Test. Default = YES (-T )
 # LZOTEST = NO
diff --git a/main.c b/main.c
index f3391a8..9b5f7db 100644
--- a/main.c
+++ b/main.c
@@ -308,7 +308,7 @@ static const char *coptions = "bcCdefghHikKlLnN:o:O:p:PrS:tTUm:vVw:z?123456789";
 int main(int argc, char *argv[])
 {
 	bool lrzcat = false, compat = false, recurse = false;
-	bool options_file = false; /* for environment and tracking of compression setting */
+	bool options_file = false, conf_file_compression_set = false; /* for environment and tracking of compression setting */
 	struct timeval start_time, end_time;
 	struct sigaction handler;
 	double seconds,total_time; // for timers
@@ -353,10 +353,8 @@ int main(int argc, char *argv[])
 		options_file = read_config(control);
 	else if (!strstr(eptr,"NOCONFIG"))
 		options_file = read_config(control);
-	if (options_file)
-		if (control->flags & FLAG_NOT_LZMA)				/* if compression set in conf file */
-			control->flags &= ~FLAG_NOT_LZMA;			/* clear compression flags (LZMA now default) */
-
+	if (options_file && (control->flags & FLAG_NOT_LZMA))		/* if some compression set in lrzip.conf    */
+		conf_file_compression_set = true;			/* need this to allow command line override */
 
 	while ((c = getopt_long(argc, argv, compat ? coptions : loptions, long_options, &i)) != -1) {
 		switch (c) {
@@ -365,9 +363,13 @@ int main(int argc, char *argv[])
 		case 'l':
 		case 'n':
 		case 'z':
-			if (control->flags & FLAG_NOT_LZMA)
+			/* If some compression was chosen in lrzip.conf, allow this one time
+			 * because conf_file_compression_set will be true
+			 */
+			if ((control->flags & FLAG_NOT_LZMA) && conf_file_compression_set == false)
 				failure("Can only use one of -l, -b, -g, -z or -n\n");
 			/* Select Compression Mode */
+			control->flags &= ~FLAG_NOT_LZMA; /* must clear all compressions first */
 			if (c == 'b')
 				control->flags |= FLAG_BZIP2_COMPRESS;
 			else if (c == 'g')
@@ -378,6 +380,8 @@ int main(int argc, char *argv[])
 				control->flags |= FLAG_NO_COMPRESS;
 			else if (c == 'z')
 				control->flags |= FLAG_ZPAQ_COMPRESS;
+			/* now FLAG_NOT_LZMA will evaluate as true */
+			conf_file_compression_set = false;
 			break;
 		case '/':							/* LZMA Compress selected */
 			control->flags &= ~FLAG_NOT_LZMA;			/* clear alternate compression flags */