Rework query functions

Now, the value/parameter retrieval function handles both GET and
POST parameters.

8 files changed, 134 insertions, 24 deletions

diff --git a/cforum.c b/cforum.c
index 7fc738e..319e9e1 100644
--- a/cforum.c
+++ b/cforum.c
@@ -6,7 +6,7 @@
 #include "ctl.h"	/* Controllers. */
 #include "err.h"	/* HTTP errors. */
 #include "site.h"	/* Site settings. Defines global struct site. */
-#include "query.h"	/* Query functions. Defines global string qs. */
+#include "query.h"	/* Query functions. Defines global struct query. */
 
 #define MAXERR 300
 
@@ -57,13 +57,13 @@ main(int argc, char *argv[])
 	sqlite3_finalize(res);
 	
 	/*
-	 * The global variable qs is set to the query string, or the
-	 * program dies. From now on, qs is assumed to be set.
+	 * The global struct query is set, or the program dies.
+	 * From now on, query is assumed to be set.
 	 */
-	setqs();
+	setquery();
 	
 	/* Handle request. */
-	if(!qs || !*qs)
+	if(!*query.string)
 		front();
 	/* INSERT CONDITIONS HERE */
 	else
diff --git a/example b/example
new file mode 100755
index 0000000..55307b9
--- /dev/null
+++ b/example
@@ -0,0 +1,12 @@
+#!/usr/bin/env perl
+
+print while <DATA>;
+
+__END__
+Content-Type: text/html
+
+<form action="cforum" method="post">
+	<p><label for="name">Name</label><input type="text" name="name" value="" id="name">
+	<p><textarea name="text" rows="8" cols="40"></textarea>
+	<p><input type="submit" value="Continue &rarr;"></p>
+</form>
\ No newline at end of file
diff --git a/front.c b/front.c
index ff6973e..7bba90a 100644
--- a/front.c
+++ b/front.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include "query.h"
 #include "site.h"
 
 void
diff --git a/query.c b/query.c
index 09e7578..bc96778 100644
--- a/query.c
+++ b/query.c
@@ -1,29 +1,94 @@
+#include <err.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include "query.h"
 
+/*
+ * Return allocated string containing next query string parameter
+ * ("key=value"). The string is truncated to max characters. If
+ * truncation occurred, the -1th character of the string is set to 1.
+ */
+char *
+nextparam(int max)
+{	
+	char *buf;
+	int i, sz;
+	static int j = 0;
+	
+	if(!query.post && !query.string[j-1])
+		return NULL;
+	
+#define STEP 256
+	
+	sz = STEP;
+	if(!(buf = malloc(1+sz))) /* Leave space for -1th character. */
+		err(1, "malloc");
+	
+	/*
+	 * buf's -1th character is set to 1 if the string
+	 * has been truncated (i.e. if input exceeded max).
+	 */
+	buf++;
+	TRUNCATED(buf) = 0;
+
+#define READ(b) (query.post? fread(b, 1, 1, stdin): (*(b) = query.string[j++]))
+
+	/* Return NULL if first character cannot be read. */
+	if(!READ(buf))
+		return NULL;
+	
+	i = 0;
+	goto loop;
+	
+	for(; READ(buf+i); i++){
+loop:
+		if(buf[i] == '&'){
+			buf[i] = 0;
+			break;
+		}
+		if(i+1 > max){
+			TRUNCATED(buf) = 1;
+			/* Skip ahead to next parameter. */
+			while(READ(buf+i+1) && buf[i+1] != '&') ;
+			break;
+		}
+		if(i+1 >= sz){
+			sz += STEP;
+			/* Remember to adjust for -1th character. */
+			if(buf--, buf = realloc(buf, 1+sz), !buf++)
+				err(1, "realloc");
+		}
+	}
+	buf[i] = 0;
+	
+	return buf;
+}
+
+/* Fill global query structure from CGI environment variables. */
 void
-setqs()
+setquery()
 {
-	qs = getenv("QUERY_STRING");
-	if(!qs){
+	query.string = getenv("QUERY_STRING");
+	if(!query.string){
 		fprintf(stderr, "no QUERY_STRING\n");
 		exit(1);
 	}
+	query.post = strcmp(getenv("REQUEST_METHOD"), "POST") == 0;
 }
 
+/*
+ * Split parameter string on equals sign and return value portion;
+ * return NULL if none found.
+ */
 char *
-query(char *key)
+split(char *param)
 {
-	char *w;
 	int n;
-	
-	for(w = strtok(qs, "&"); w; w = strtok(NULL, "&")){
-		n = strcspn(w, "=");
-		if(strncmp(w, key, n) == 0)
-			return w + n + (w[n] == '=');
-	}
-	
-	return NULL;
+
+	n = strcspn(param, "=");
+	if(!param[n])
+		return NULL;
+	param[n] = 0;
+	return param+n+1;
 }
\ No newline at end of file
diff --git a/query.h b/query.h
index 81662a8..98fedb0 100644
--- a/query.h
+++ b/query.h
@@ -1,4 +1,10 @@
-char *qs;
+#define TRUNCATED(s) s[-1]
 
-void setqs(void);
-char *query(char *);
\ No newline at end of file
+struct query{
+	int post;
+	char *string;
+} query;
+
+char *nextparam(int);
+void setquery(void);
+char *split(char *);
\ No newline at end of file
diff --git a/site.h b/site.h
index e5dba32..f590bad 100644
--- a/site.h
+++ b/site.h
@@ -1,3 +1,3 @@
-struct site {
+struct site{
 	char *name;
 } site;
\ No newline at end of file
diff --git a/t/front.t b/t/front.t
index ed6fbf8..0a372a6 100644
--- a/t/front.t
+++ b/t/front.t
@@ -1,2 +1,16 @@
 <h1><%= site.name %></h1>
-<% printf("Hello world!"); %>
\ No newline at end of file
+<% printf("Hello world!"); %>
+<br>
+Request method: <%= getenv("REQUEST_METHOD") %>
+<br>
+<%
+	char *a, *b, *bv;
+	a = nextparam(512);
+	printf("%s (%d)<br>", a, TRUNCATED(a));
+	b = nextparam(512);
+	printf("%s (%d)<br>", b, TRUNCATED(b));
+	bv = split(b);
+	printf("'%s' contains '%s'<br>", b, bv);
+	printf("Next: %s\n", nextparam(512));
+	printf("Next: %s\n", nextparam(512));
+%>
\ No newline at end of file
diff --git a/t/front.tc b/t/front.tc
index 0d7aec3..89e665a 100644
--- a/t/front.tc
+++ b/t/front.tc
@@ -1,4 +1,16 @@
 printf("<h1>");
 printf("%s",  site.name );
 printf("</h1>\n");
- printf("Hello world!"); printf("\n");
+ printf("Hello world!"); printf("\n<br>\nRequest method: ");
+printf("%s",  getenv("REQUEST_METHOD") );
+printf("<br>\n");
+	char *a, *b, *bv;
+	a = nextparam(512);
+	printf("%s (%d)<br>", a, TRUNCATED(a));
+	b = nextparam(512);
+	printf("%s (%d)<br>", b, TRUNCATED(b));
+	bv = split(b);
+	printf("'%s' contains '%s'<br>", b, bv);
+	printf("Next: %s\n", nextparam(512));
+	printf("Next: %s\n", nextparam(512));
+printf("\n");