Decompressors: get rid of set_error_fn() macro

From: Lasse Collin <lasse.collin@xxxxxxxxxxx>

set_error_fn() is a useless complication. Only unlzma.c had some use
for it and that was easy to change too.

This also gets rid of the static function pointer "error".

Signed-off-by: Lasse Collin <lasse.collin@xxxxxxxxxxx>
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/common/decompress.h
+++ b/xen/common/decompress.h
@@ -10,9 +10,6 @@
 #define INIT __init
 #define INITDATA __initdata
 
-static void(*__initdata error)(const char *);
-#define set_error_fn(x) error = x;
-
 #define malloc xmalloc_bytes
 #define free xfree
 
--- a/xen/common/bunzip2.c
+++ b/xen/common/bunzip2.c
@@ -666,13 +666,12 @@ STATIC int INIT bunzip2(unsigned char *b
 			int(*flush)(void*, unsigned int),
 			unsigned char *outbuf,
 			unsigned int *pos,
-			void(*error_fn)(const char *x))
+			void(*error)(const char *x))
 {
 	struct bunzip_data *bd;
 	int i = -1;
 	unsigned char *inbuf;
 
-	set_error_fn(error_fn);
 	if (flush)
 		outbuf = malloc(BZIP2_IOBUF_SIZE);
 
--- a/xen/common/unlzma.c
+++ b/xen/common/unlzma.c
@@ -67,6 +67,7 @@ struct rc {
 	uint32_t code;
 	uint32_t range;
 	uint32_t bound;
+	void (*error)(const char *);
 };
 
 
@@ -85,7 +86,7 @@ static void INIT rc_read(struct rc *rc)
 {
 	rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE);
 	if (rc->buffer_size <= 0)
-		error("unexpected EOF");
+		rc->error("unexpected EOF");
 	rc->ptr = rc->buffer;
 	rc->buffer_end = rc->buffer + rc->buffer_size;
 }
@@ -529,7 +530,7 @@ STATIC int INIT unlzma(unsigned char *bu
 		       int(*flush)(void*, unsigned int),
 		       unsigned char *output,
 		       unsigned int *posp,
-		       void(*error_fn)(const char *x)
+		       void(*error)(const char *x)
 	)
 {
 	struct lzma_header header;
@@ -545,7 +546,7 @@ STATIC int INIT unlzma(unsigned char *bu
 	unsigned char *inbuf;
 	int ret = -1;
 
-	set_error_fn(error_fn);
+	rc.error = error;
 
 	if (buf)
 		inbuf = buf;
--- a/xen/common/unlzo.c
+++ b/xen/common/unlzo.c
@@ -105,7 +105,7 @@ STATIC int INIT unlzo(u8 *input, unsigne
 		      int (*fill) (void *, unsigned int),
 		      int (*flush) (void *, unsigned int),
 		      u8 *output, unsigned int *posp,
-		      void (*error_fn) (const char *x))
+		      void (*error) (const char *x))
 {
 	u8 skip = 0, r = 0;
 	u32 src_len, dst_len;
@@ -113,8 +113,6 @@ STATIC int INIT unlzo(u8 *input, unsigne
 	u8 *in_buf, *in_buf_save, *out_buf;
 	int ret = -1;
 
-	set_error_fn(error_fn);
-
 	if (output) {
 		out_buf = output;
 	} else if (!flush) {
--- a/xen/common/unxz.c
+++ b/xen/common/unxz.c
@@ -161,15 +161,13 @@ STATIC int INIT unxz(unsigned char *in, 
 		     int (*fill)(void *dest, unsigned int size),
 		     int (*flush)(void *src, unsigned int size),
 		     unsigned char *out, unsigned int *in_used,
-		     void (*error_fn)(const char *x))
+		     void (*error)(const char *x))
 {
 	struct xz_buf b;
 	struct xz_dec *s;
 	enum xz_ret ret;
 	bool_t must_free_in = false;
 
-	set_error_fn(error_fn);
-
 	xz_crc32_init();
 
 	if (in_used != NULL)