gcc -o myprogram myprogram.c -lmxml
If you have the pkg-config software installed, you can use it to determine the proper compiler and linker options for your installation:
gcc `pkg-config --cflags mxml` -o myprogram myprogram.c `pkg-config --libs mxml`
+gcc `pkg-config --cflags mxml4` -o myprogram myprogram.c `pkg-config --libs mxml4`
Loading an XML File
You load an XML file using the mxmlLoadFile function:
@@ -1151,12 +1151,15 @@ mxmlSAXLoadString(mxml_node_t *top, const void *sax_data);
Each function works like the corresponding mxmlLoad function but uses a callback to process each node as it is read. The callback function receives the node, an event code, and a user data pointer you supply:
void
+Each function works like the corresponding mxmlLoad function but uses a callback to process each node as it is read. The callback function receives the node, an event code, and a user data pointer you supply and returns true to continue processing or false to stop:
+bool
sax_cb(mxml_node_t *node, mxml_sax_event_t event,
void *data)
{
... do something ...
+
+ // Continue processing...
+ return (true);
}
The event will be one of the following:
@@ -1165,7 +1168,7 @@ sax_cb(mxml_node_t *node, mxml_sax_event_t event,
MXML_SAX_EVENT_COMMENT: A comment was just read.
MXML_SAX_EVENT_DATA: Data ( --------------------, integer, opaque, real, or text) was just read.
+MXML_SAX_EVENT_DATA: Data (integer, opaque, real, or text) was just read.
MXML_SAX_EVENT_DECLARATION: A declaration was just read.
Elements are released after the close element is processed. All other nodes are released after they are processed. The SAX callback can retain the node using the mxmlRetain function. For example, the following SAX callback will retain all nodes, effectively simulating a normal in-memory load:
-void
+bool
sax_cb(mxml_node_t *node, mxml_sax_event_t event,
void *data)
{
if (event != MXML_SAX_ELEMENT_CLOSE)
mxmlRetain(node);
+
+ return (true);
}
More typically the SAX callback will only retain a small portion of the document that is needed for post-processing. For example, the following SAX callback will retain the title and headings in an XHTML file. It also retains the (parent) elements like <html>, <head>, and <body>, and processing directives like <?xml ... ?> and declarations like <!DOCTYPE ... >:
-void
+bool
sax_cb(mxml_node_t *node, mxml_sax_event_t event,
void *data)
{
@@ -1226,6 +1231,8 @@ sax_cb(mxml_node_t *node, mxml_sax_event_t event,
mxmlRetain(node);
}
}
+
+ return (true);
}
The resulting skeleton document tree can then be searched just like one loaded using the mxmlLoad functions. For example, a filter that reads an XHTML document from stdin and then shows the title and headings in the document would look like:
@@ -1277,7 +1284,9 @@ print_children(mxml_node_t *parent)
Migrating from Mini-XML v3.x
The following incompatible API changes were made in Mini-XML v4.0:
-SAX events are not named MXML_SAX_EVENT_foo instead of MXML_SAX_foo.
+SAX events are now named MXML_SAX_EVENT_foo instead of MXML_SAX_foo.
+SAX callbacks now return a boolean value.
Node types are now named MXML_TYPE_foo instead of MXML_foo.
mxml_sax_cb_t
SAX callback function
-typedef void (*mxml_sax_cb_t)(mxml_node_t *, mxml_sax_event_t, void *);
+typedef bool (*mxml_sax_cb_t)(mxml_node_t *, mxml_sax_event_t, void *);
mxml_sax_event_t
SAX event type.
diff --git a/mxml-file.c b/mxml-file.c
index 5f7f78b..8a93ab6 100644
--- a/mxml-file.c
+++ b/mxml-file.c
@@ -1341,7 +1341,8 @@ mxml_load_data(
if (sax_cb)
{
- (*sax_cb)(node, MXML_SAX_EVENT_DATA, sax_data);
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_DATA, sax_data))
+ goto error;
if (!mxmlRelease(node))
node = NULL;
@@ -1367,7 +1368,8 @@ mxml_load_data(
if (sax_cb)
{
- (*sax_cb)(node, MXML_SAX_EVENT_DATA, sax_data);
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_DATA, sax_data))
+ goto error;
if (!mxmlRelease(node))
node = NULL;
@@ -1464,7 +1466,8 @@ mxml_load_data(
if (sax_cb)
{
- (*sax_cb)(node, MXML_SAX_EVENT_COMMENT, sax_data);
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_COMMENT, sax_data))
+ goto error;
if (!mxmlRelease(node))
node = NULL;
@@ -1520,7 +1523,8 @@ mxml_load_data(
if (sax_cb)
{
- (*sax_cb)(node, MXML_SAX_EVENT_CDATA, sax_data);
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_CDATA, sax_data))
+ goto error;
if (!mxmlRelease(node))
node = NULL;
@@ -1570,7 +1574,8 @@ mxml_load_data(
if (sax_cb)
{
- (*sax_cb)(node, MXML_SAX_EVENT_DIRECTIVE, sax_data);
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_DIRECTIVE, sax_data))
+ goto error;
if (strncmp(node->value.directive, "xml ", 4) && !mxmlRelease(node))
node = NULL;
@@ -1645,7 +1650,8 @@ mxml_load_data(
if (sax_cb)
{
- (*sax_cb)(node, MXML_SAX_EVENT_DECLARATION, sax_data);
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_DECLARATION, sax_data))
+ goto error;
if (!mxmlRelease(node))
node = NULL;
@@ -1686,7 +1692,8 @@ mxml_load_data(
if (sax_cb)
{
- (*sax_cb)(node, MXML_SAX_EVENT_ELEMENT_CLOSE, sax_data);
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_ELEMENT_CLOSE, sax_data))
+ goto error;
if (!mxmlRelease(node))
{
@@ -1737,7 +1744,10 @@ mxml_load_data(
}
if (sax_cb)
- (*sax_cb)(node, MXML_SAX_EVENT_ELEMENT_OPEN, sax_data);
+ {
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_ELEMENT_OPEN, sax_data))
+ goto error;
+ }
if (!first)
first = node;
@@ -1757,7 +1767,8 @@ mxml_load_data(
}
else if (sax_cb)
{
- (*sax_cb)(node, MXML_SAX_EVENT_ELEMENT_CLOSE, sax_data);
+ if (!(*sax_cb)(node, MXML_SAX_EVENT_ELEMENT_CLOSE, sax_data))
+ goto error;
if (!mxmlRelease(node))
{
diff --git a/mxml.h b/mxml.h
index 71427e4..71634b1 100644
--- a/mxml.h
+++ b/mxml.h
@@ -120,7 +120,7 @@ typedef mxml_type_t (*mxml_load_cb_t)(mxml_node_t *);
typedef const char *(*mxml_save_cb_t)(mxml_node_t *, int);
// Save callback function
-typedef void (*mxml_sax_cb_t)(mxml_node_t *, mxml_sax_event_t, void *);
+typedef bool (*mxml_sax_cb_t)(mxml_node_t *, mxml_sax_event_t, void *);
// SAX callback function