XML-Parser für resourcedateien

src/common/util/xml.c

@@ -0,0 +1,237 @@
+#include <config.h>
+#include "xml.h"
+
+/* libc includes */
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+static int 
+__cberror(const struct xml_stack * stack, const char* parsed, unsigned int line, int error)
+{
+	fprintf(stderr, "Error #%d in line %u while parsing \"%s\"\n", -error, line, parsed);
+	return error;
+}
+
+static xml_tag * 
+make_tag(const char * name)
+{
+	xml_tag * tag = calloc(sizeof(xml_tag), 1);
+	tag->name = strdup(name);
+	return tag;
+}
+
+static void
+push_tag(xml_stack ** ostack, xml_tag * tag)
+{
+	xml_stack * stack = calloc(sizeof(xml_stack), 1);
+	stack->next = *ostack;
+	stack->tag = tag;
+	*ostack = stack;
+}
+
+static void
+free_attribs(xml_attrib * xa)
+{
+	free(xa->name);
+	free(xa->value);
+	free(xa);
+}
+
+static void
+free_tag(xml_tag * tag)
+{
+	while (tag->attribs) {
+		xml_attrib * p = tag->attribs;
+		tag->attribs = tag->attribs->next;
+		free_attribs(p);
+	}
+	free(tag->name);
+	free(tag);
+}
+
+static xml_attrib *
+make_attrib(xml_tag * tag, const char * name)
+{
+	xml_attrib * xa = calloc(sizeof(xml_attrib), 1);
+	xa->name = strdup(name);
+	xa->next = tag->attribs;
+	return tag->attribs = xa;
+}
+
+static xml_tag *
+pop_tag(xml_stack ** ostack)
+{
+	xml_stack * stack = *ostack;
+	xml_tag * tag = stack->tag;
+	*ostack = stack->next;
+	free(stack);
+	return tag;
+}
+
+int
+xml_parse(FILE * stream, struct xml_callbacks * cb)
+{
+	xml_stack * stack = NULL;
+	enum { TAG, ENDTAG, ATNAME, ATVALUE, PLAIN } state = PLAIN;
+	char tokbuffer[1024];
+	char * pos = tokbuffer;
+	int quoted = 0;
+	unsigned int line = 0;
+	xml_tag * tag = NULL;
+	xml_attrib * attrib = NULL;
+	int (*cb_error)(const struct xml_stack*, const char*, unsigned int, int) = __cberror;
+	if (cb && cb->error) cb_error = cb->error;
+
+	for (;;) {
+		int reparse;
+		int c = fgetc(stream);
+		if (c=='\n') {
+			++line;
+		} else if (c==EOF) {
+			if (state==PLAIN) {
+				*pos='\0';
+				if (cb && cb->plaintext && pos!=tokbuffer) cb->plaintext(stack, tokbuffer);
+				break;
+			} else {
+				*pos='\0';
+				return cb_error(stack, tokbuffer, line, XML_BROKENSTREAM);
+			}
+		}
+		do {
+			reparse = 0;
+			switch (state) {
+			case ATVALUE:
+				switch (c) {
+				case '<':
+				case '/':
+					*pos='\0';
+					return cb_error(stack, tokbuffer, line, XML_INVALIDCHAR);
+				case '"':
+					quoted = !quoted;
+					break;
+				case '>':
+					if (quoted) {
+						*pos='\0';
+						return cb_error(stack, tokbuffer, line, XML_INVALIDCHAR);
+					}
+					state = TAG;
+					/* intentional fallthrough */
+				default:
+					if (quoted) *pos++ = (char)c;
+					else {
+						if (isspace(c) || c=='>') {
+							assert(attrib || !"internal error");
+							*pos='\0';
+							attrib->value = strdup(tokbuffer);
+							state = TAG;
+							pos = tokbuffer;
+							if (c=='>') reparse = 1;
+						}
+					}
+				}
+				break; /* case ATVALUE */
+			case ATNAME:
+				switch (c) {
+				case '=':
+					*pos='\0';
+					assert(tag || !"internal error");
+					attrib = make_attrib(tag, tokbuffer);
+					state = ATVALUE;
+					pos = tokbuffer;
+					break;
+				case '>':
+				case '<':
+				case '/':
+					*pos='\0';
+					return cb_error(stack, tokbuffer, line, XML_INVALIDCHAR);
+				default:
+					if (isspace(c)) {
+						*pos='\0';
+						return cb_error(stack, tokbuffer, line, XML_INVALIDCHAR);
+					}
+					*pos++ = (char)c;
+				}
+				break; /* case ATNAME */
+			case PLAIN:
+				switch (c) {
+				case '<':
+					if (cb && cb->plaintext && pos!=tokbuffer) {
+						*pos = '\0';
+						cb->plaintext(stack, tokbuffer);
+					}
+					state = TAG;
+					tag = NULL;
+					pos = tokbuffer;
+					break;
+				case '>':
+					*pos='\0';
+					return cb_error(stack, tokbuffer, line, XML_INVALIDCHAR);
+				default:
+					*pos++ = (char)c;
+				}
+				break; /* case PLAIN */
+			case TAG:
+				switch (c) {
+				case '/':
+					if (pos==tokbuffer) state = ENDTAG;
+					else {
+						*pos='\0';
+						return cb_error(stack, tokbuffer, line, XML_INVALIDCHAR);
+					}
+					break;
+				case '>':
+					if (tag==NULL) {
+						*pos='\0';
+						push_tag(&stack, make_tag(tokbuffer));
+					}
+					if (cb && cb->tagbegin) cb->tagbegin(stack);
+					state = PLAIN;
+					pos = tokbuffer;
+					break;
+				default:
+					if (isspace(c)) {
+						if (tag==NULL) {
+							*pos='\0';
+							push_tag(&stack, tag = make_tag(tokbuffer));
+							state = ATNAME;
+							pos = tokbuffer;
+						}
+					} else {
+						if (tag!=NULL) {
+							state = ATNAME;
+							pos = tokbuffer;
+							reparse = 1;
+						}
+						else *pos++ = (char)c;
+					}
+				}
+				break; /* case TAG */
+			case ENDTAG:
+				switch (c) {
+				case '>':
+					*pos = '\0';
+					while (stack && strcmp(stack->tag->name, tokbuffer)!=0) free_tag(pop_tag(&stack));
+					if (stack==NULL) return cb_error(stack, tokbuffer, line, XML_NESTINGERROR);
+					if (cb && cb->tagend) cb->tagend(stack);
+					free_tag(pop_tag(&stack));
+					state = PLAIN;
+					pos = tokbuffer;
+					break;
+				case '<':
+				case ' ':
+				case '=':
+				case '/':
+					*pos='\0';
+					return cb_error(stack, tokbuffer, line, XML_INVALIDCHAR);
+				default:
+					*pos++ = (char)c;
+				}
+				break; /* case ENDTAG */
+			} /* switch(state) */
+		} while (reparse);
+	}  /* for(;;) */
+	return XML_OK; /* SUCCESS */
+}

src/common/util/xml.h

@@ -0,0 +1,33 @@
+typedef struct xml_stack {
+	struct xml_stack * next;
+	struct xml_tag * tag;
+} xml_stack;
+
+typedef struct xml_tag {
+	char * name;
+	struct xml_attrib * attribs;
+} xml_tag;
+
+typedef struct xml_attrib {
+	struct xml_attrib * next;
+	char * name;
+	char * value;
+} xml_attrib;
+
+#define XML_OK 0
+#define XML_INVALIDCHAR -1
+#define XML_NESTINGERROR -2
+#define XML_BROKENSTREAM -3
+
+/* callbacks */
+typedef struct xml_callbacks {
+	int (*plaintext)(const struct xml_stack *, const char*);
+	int (*tagbegin)(const struct xml_stack *);
+	int (*tagend)(const struct xml_stack *);
+	int (*error)(const struct xml_stack *, const char*, unsigned int, int);
+} xml_callbacks;
+
+/* parser */
+#include <stdio.h>
+extern int xml_parse(FILE * stream, struct xml_callbacks *);
+