Make the xslt style sheet finding search a set of possible paths

This allows us to install the xslt files in multiple places.  Right now
the path defaults to the subsurface xslt install directory, the relative
directory "xslt" and the current working directory.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 49 insertions, 1 deletions

diff --git a/parse-xml.c b/parse-xml.c
index ddf93a4b1..bc4d4c546 100644
--- a/parse-xml.c
+++ b/parse-xml.c
@@ -3,6 +3,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <errno.h>
+#include <unistd.h>
 #define __USE_XOPEN
 #include <time.h>
 #include <libxml/parser.h>
@@ -1484,6 +1485,53 @@ void parse_xml_init(void)
 }
 
 #ifdef XSLT
+
+/* Maybe we'll want a environment variable that can override this.. */
+static const char *xslt_path = XSLT ":xslt:.";
+
+static xsltStylesheetPtr try_get_stylesheet(const char *path, int len, const char *name)
+{
+	xsltStylesheetPtr ret;
+	int namelen = strlen(name);
+	char *filename = malloc(len+1+namelen+1);
+
+	if (!filename)
+		return NULL;
+
+	memcpy(filename, path, len);
+	filename[len] = G_DIR_SEPARATOR;
+	memcpy(filename + len + 1, name, namelen+1);
+
+	ret = NULL;
+	if (!access(filename, R_OK))
+		ret = xsltParseStylesheetFile(filename);
+	free(filename);
+
+	return ret;
+}
+
+static xsltStylesheetPtr get_stylesheet(const char *name)
+{
+	const char *path = xslt_path, *next;
+
+	do {
+		int len;
+		xsltStylesheetPtr ret;
+
+		next = strchr(path, ':');
+		len = strlen(path);
+		if (next) {
+			len = next - path;
+			next++;
+		}
+		ret = try_get_stylesheet(path, len, name);
+		if (ret)
+			return ret;
+	} while ((path = next) != NULL);
+
+	return NULL;
+}
+
 xmlDoc *test_xslt_transforms(xmlDoc *doc)
 {
 	xmlDoc *transformed;
@@ -1491,7 +1539,7 @@ xmlDoc *test_xslt_transforms(xmlDoc *doc)
 	xmlNode *root_element = xmlDocGetRootElement(doc);
 	if (strcasecmp(root_element->name, "JDiveLog") == 0) {
 		xmlSubstituteEntitiesDefault(1);
-		xslt = xsltParseStylesheetFile(XSLT G_DIR_SEPARATOR_S "jdivelog2subsurface.xslt");
+		xslt = get_stylesheet("jdivelog2subsurface.xslt");
 		if (xslt == NULL)
 			return doc;
 		transformed = xsltApplyStylesheet(xslt, doc, NULL);