Re: [xslt] str:replace implementation
- From: joel reed <joel reed ddiworld com>
- To: veillard redhat com, The Gnome XSLT library mailing-list <xslt gnome org>
- Subject: Re: [xslt] str:replace implementation
- Date: Tue, 09 Jan 2007 15:05:57 -0500
Daniel Veillard wrote:
On Mon, Jan 08, 2007 at 04:04:40PM -0500, joel reed wrote:
Please find attached an implementation of the exslt.org str:replace
function and 7 test cases.
Okay, thanks !
Documentation on the function can be found here:
http://www.exslt.org/str/functions/replace/index.html
In that spec, I did not implement these last two sentences: "The longest
search strings are replaced first. If a search string is empty, then the
equivalently positioned replacement node is inserted between every
character in the string." I felt the added code complexity and
performance hit was not worth the impact at this time.
I guess there is a bug there:
xmlUTF8Strlen() counts the number of characters in an UTF-8 encoded
string, not the number of bytes. So you should not use it as the
value of the increment of the xmlChar * , but use xmlStrlen() instead in
exsltStrReplaceInternal()
fixed in attached patch.
I also added the rest to the makefile.am in tests/exslt/strings, in my version
compiled with memory debug it points out a memory leak:
fixed in attached patch.
paphio:~/XSLT/tests/exslt/strings -> make tests
## Running exslt string tests
replace.1 result
MEMORY ALLOCATED : 1218, MAX was 171024
paphio:~/XSLT/tests/exslt/strings -> cat .memdump
03:04:43 PM
MEMORY ALLOCATED : 1218, MAX was 171020
BLOCK NUMBER SIZE TYPE
0 1203 11 malloc() in none(0) "j, j, j, j"
1 1200 66 malloc() in none(0) "fum"
2 1197 66 malloc() in none(0) "fo"
3 1194 66 malloc() in none(0) "fi"
4 1191 66 malloc() in none(0) "fee"
5 1188 17 malloc() in none(0) "fee, fi, fo, fum"
6 1187 2 malloc() in none(0) "j"
7 1185 40 malloc() in none(0)
8 1184 12 malloc() in none(0) pointer to #1185 at index 8
9 1179 34 malloc() in none(0) "tee, eye, billow, a longe"
10 1176 66 malloc() in none(0) "a longer string"
11 1174 66 malloc() in none(0) "fum"
12 1171 66 malloc() in none(0) "billow"
13 1169 66 malloc() in none(0) "fo"
etc...
I start looking at the code with the debugger (following the instructions
at http://xmlsoft.org/xmlmem.html) and it is clear:
- that the argument popped from XPath stack are not freed in the normal path
- it seems that there is no free either in case of error, just doing
xmlXPathSetTypeError() and return but no deallocations
Plus there is a number of case, where the args can be strings or nodesets, it's
probably better if you could check all the deallocation paths and provide
another patch once those issues have been checked that would be nice !
fixed in attached patch.
thanks again for the feedback. when i run make tests now i get an empty
.memdump file. i hope this version looks better to you.
jr
diff --git a/libexslt/strings.c b/libexslt/strings.c
index c867f9c..af7aa88 100644
--- a/libexslt/strings.c
+++ b/libexslt/strings.c
@@ -495,6 +495,143 @@ exsltStrConcatFunction (xmlXPathParserCo
}
/**
+ * exsltStrReplaceInternal:
+ * @str: string to modify
+ * @searchStr: string to find
+ * @replaceStr: string to replace occurrences of searchStr
+ *
+ * Search and replace string function used by exsltStrReplaceFunction
+ */
+static xmlChar*
+exsltStrReplaceInternal(const xmlChar* str, const xmlChar* searchStr,
+ const xmlChar* replaceStr)
+{
+ const xmlChar *curr, *next;
+ xmlChar *ret = NULL;
+ int searchStrSize;
+
+ curr = str;
+ searchStrSize = xmlStrlen(searchStr);
+
+ do {
+ next = xmlStrstr(curr, searchStr);
+ if (next == NULL) {
+ ret = xmlStrcat (ret, curr);
+ break;
+ }
+
+ ret = xmlStrncat (ret, curr, next - curr);
+ ret = xmlStrcat (ret, replaceStr);
+ curr = next + searchStrSize;
+ } while (*curr != 0);
+
+ return ret;
+}
+/**
+ * exsltStrReplaceFunction:
+ * @ctxt: an XPath parser context
+ * @nargs: the number of arguments
+ *
+ * Takes a string, and two node sets and returns the string with all strings in
+ * the first node set replaced by all strings in the second node set.
+ */
+static void
+exsltStrReplaceFunction (xmlXPathParserContextPtr ctxt, int nargs) {
+ xmlChar *str = NULL, *searchStr = NULL, *replaceStr = NULL;
+ xmlNodeSetPtr replaceSet = NULL, searchSet = NULL;
+ xmlChar *ret = NULL, *retSwap = NULL;
+ int i;
+
+ if (nargs != 3) {
+ xmlXPathSetArityError(ctxt);
+ return;
+ }
+
+ /* pull out replace argument */
+ if (!xmlXPathStackIsNodeSet(ctxt)) {
+ replaceStr = xmlXPathPopString(ctxt);
+ }
+ else {
+ replaceSet = xmlXPathPopNodeSet(ctxt);
+ if (xmlXPathCheckError(ctxt)) {
+ xmlXPathSetTypeError(ctxt);
+ goto fail;
+ }
+ }
+
+ /* behavior driven by search argument from here on */
+ if (!xmlXPathStackIsNodeSet(ctxt)) {
+ searchStr = xmlXPathPopString(ctxt);
+ str = xmlXPathPopString(ctxt);
+
+ if (replaceStr == NULL) {
+ xmlXPathSetTypeError(ctxt);
+ goto fail;
+ }
+
+ ret = exsltStrReplaceInternal(str, searchStr, replaceStr);
+ }
+ else {
+ searchSet = xmlXPathPopNodeSet(ctxt);
+ if (searchSet == NULL || xmlXPathCheckError(ctxt)) {
+ xmlXPathSetTypeError(ctxt);
+ goto fail;
+ }
+
+ str = xmlXPathPopString(ctxt);
+ ret = xmlStrdup(str);
+
+ for (i = 0; i < searchSet->nodeNr; i++) {
+
+ searchStr = xmlXPathCastNodeToString(searchSet->nodeTab[i]);
+
+ if (replaceSet != NULL) {
+ replaceStr = NULL;
+ if (i <= replaceSet->nodeNr) {
+ replaceStr = xmlXPathCastNodeToString(replaceSet->nodeTab[i]);
+ }
+
+ retSwap = exsltStrReplaceInternal(ret, searchStr, replaceStr);
+
+ if (replaceStr != NULL) {
+ xmlFree(replaceStr);
+ replaceStr = NULL;
+ }
+ }
+ else {
+ retSwap = exsltStrReplaceInternal(ret, searchStr, replaceStr);
+ }
+
+ xmlFree(ret);
+ if (searchStr != NULL) {
+ xmlFree(searchStr);
+ searchStr = NULL;
+ }
+
+ ret = retSwap;
+ }
+
+ if (replaceSet != NULL)
+ xmlXPathFreeNodeSet(replaceSet);
+
+ if (searchSet != NULL)
+ xmlXPathFreeNodeSet(searchSet);
+ }
+
+ xmlXPathReturnString(ctxt, ret);
+
+ fail:
+ if (replaceStr != NULL)
+ xmlFree(replaceStr);
+
+ if (searchStr != NULL)
+ xmlFree(searchStr);
+
+ if (str != NULL)
+ xmlFree(str);
+}
+
+/**
* exsltStrRegister:
*
* Registers the EXSLT - Strings module
@@ -523,4 +660,7 @@ exsltStrRegister (void) {
xsltRegisterExtModuleFunction ((const xmlChar *) "concat",
EXSLT_STRINGS_NAMESPACE,
exsltStrConcatFunction);
+ xsltRegisterExtModuleFunction ((const xmlChar *) "replace",
+ EXSLT_STRINGS_NAMESPACE,
+ exsltStrReplaceFunction);
}
diff --git a/tests/exslt/strings/Makefile.am b/tests/exslt/strings/Makefile.am
index 6926802..5bdbd2a 100644
--- a/tests/exslt/strings/Makefile.am
+++ b/tests/exslt/strings/Makefile.am
@@ -7,7 +7,8 @@ EXTRA_DIST = \
tokenize.1.xml tokenize.1.xsl tokenize.1.out \
tokenize.2.xml tokenize.2.xsl tokenize.2.out \
tokenize.3.xml tokenize.3.xsl tokenize.3.out \
- split.1.xml split.1.xsl split.1.out
+ split.1.xml split.1.xsl split.1.out \
+ replace.1.xml replace.1.xsl replace.1.out
all:
diff --git a/tests/exslt/strings/Makefile.in b/tests/exslt/strings/Makefile.in
index 167160e..3a112c9 100644
--- a/tests/exslt/strings/Makefile.in
+++ b/tests/exslt/strings/Makefile.in
@@ -213,7 +213,8 @@ EXTRA_DIST = \
tokenize.1.xml tokenize.1.xsl tokenize.1.out \
tokenize.2.xml tokenize.2.xsl tokenize.2.out \
tokenize.3.xml tokenize.3.xsl tokenize.3.out \
- split.1.xml split.1.xsl split.1.out
+ split.1.xml split.1.xsl split.1.out \
+ replace.1.xml replace.1.xsl replace.1.out
all: all-am
diff --git a/tests/exslt/strings/replace.1.out b/tests/exslt/strings/replace.1.out
new file mode 100644
index 0000000..076d110
--- /dev/null
+++ b/tests/exslt/strings/replace.1.out
@@ -0,0 +1,22 @@
+<?xml version="1.0"?>
+<out>;
+ str:replace('a, simple, list', ', ', '-')
+ a-simple-list
+
+ str:replace('a, simple, list', 'a, ', 'the ')
+ the simple, list
+
+ str:replace('a, simple, list', 'list', 'array')
+ a, simple, array
+
+ str:replace('a, simple, list', 'i', 'I')
+ a, sImple, lIst
+
+ str:replace('a, simple, list', ', ', '')
+ asimplelist
+
+ str:replace('fee, fi, fo, fum', $x, $y)
+ tee, eye, billow, a longer string
+
+ str:replace('fee, fi, fo, fum', $x, 'j')
+ j, j, j, j</out>
diff --git a/tests/exslt/strings/replace.1.xml b/tests/exslt/strings/replace.1.xml
new file mode 100644
index 0000000..6371161
--- /dev/null
+++ b/tests/exslt/strings/replace.1.xml
@@ -0,0 +1,12 @@
+<doc>
+ <strings>
+ <x>fee</x>
+ <x>fi</x>
+ <x>fo</x>
+ <x>fum</x>
+ <y>tee</y>
+ <y>eye</y>
+ <y>billow</y>
+ <y>a longer string</y>
+ </strings>
+</doc>
diff --git a/tests/exslt/strings/replace.1.xsl b/tests/exslt/strings/replace.1.xsl
new file mode 100644
index 0000000..0c9e86c
--- /dev/null
+++ b/tests/exslt/strings/replace.1.xsl
@@ -0,0 +1,36 @@
+<?xml version="1.0"?>
+<xsl:stylesheet version="1.0"
+ xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
+ xmlns:str="http://exslt.org/strings";
+ exclude-result-prefixes="str">
+
+<xsl:template match="/">
+ <xsl:variable name="x" select="doc/strings/x"/>
+ <xsl:variable name="y" select="doc/strings/y"/>
+
+<out>;
+ str:replace('a, simple, list', ', ', '-')
+ <xsl:copy-of select="str:replace('a, simple, list', ', ', '-')"/>
+
+ str:replace('a, simple, list', 'a, ', 'the ')
+ <xsl:copy-of select="str:replace('a, simple, list', 'a, ', 'the ')"/>
+
+ str:replace('a, simple, list', 'list', 'array')
+ <xsl:copy-of select="str:replace('a, simple, list', 'list', 'array')"/>
+
+ str:replace('a, simple, list', 'i', 'I')
+ <xsl:copy-of select="str:replace('a, simple, list', 'i', 'I')"/>
+
+ str:replace('a, simple, list', ', ', '')
+ <xsl:copy-of select="str:replace('a, simple, list', ', ', '')"/>
+
+ str:replace('fee, fi, fo, fum', $x, $y)
+ <xsl:copy-of select="str:replace('fee, fi, fo, fum', $x, $y)" />
+
+ str:replace('fee, fi, fo, fum', $x, 'j')
+ <xsl:copy-of select="str:replace('fee, fi, fo, fum', $x, 'j')" />
+
+</out>
+</xsl:template>
+
+</xsl:stylesheet>
begin:vcard
fn:Joel Reed
n:Reed;Joel
org:Development Dimensions International;E-Systems
adr;dom:;;1225 Washington Pike;Bridgeville;PA;15017
title:Manager, E-Products R&D
tel;work:412-257-3881
note;quoted-printable:Unleashing Executive Talent. Hiring & Promoting The Best.=0D=0A=
Developing Extraordinary Leaders. Discover how at www.ddiworld.com
x-mozilla-html:FALSE
version:2.1
end:vcard
[
Date Prev][
Date Next] [
Thread Prev][
Thread Next]
[
Thread Index]
[
Date Index]
[
Author Index]
