Implements CGI in C

2 files changed, 241 insertions, 0 deletions

diff --git a/tools/Makefile.am b/tools/Makefile.am
new file mode 100644
index 0000000..8863b29
--- /dev/null
+++ b/tools/Makefile.am
@@ -0,0 +1,7 @@
+
+bin_PROGRAMS = rrdui-cgi
+
+
+rrdui_cgi_SOURCES = rrdui-cgi.c \
+	../common/config-parser.c ../common/config-parser.h \
+	../common/compat.c ../common/compat.h ../common/usuals.h
diff --git a/tools/rrdui-cgi.c b/tools/rrdui-cgi.c
new file mode 100644
index 0000000..a2e7407
--- /dev/null
+++ b/tools/rrdui-cgi.c
@@ -0,0 +1,234 @@
+
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <err.h>
+#include <unistd.h>
+
+static char* conf_directory = NULL;
+static char* work_directory = NULL;
+
+typedef struct _graph
+{
+	const char* name;
+	char* title;
+	int width;
+	int height;
+	int interval;
+	char* category;
+
+	struct _graph *next;
+}
+graph;
+
+static graph* allgraphs = NULL;
+
+/* -----------------------------------------------------------------------------
+ * CONFIG PARSING
+ */
+
+int cfg_value(const char* filename, const char* header, const char* name,
+              char* value, void* data)
+{
+	static graph* gr = NULL;
+
+	/*  called like this after ever file */
+	if (!header)
+	{
+		/* add to the list */
+		gr->next = allgraphs;
+		allgraphs = gr;
+
+		gr = NULL;
+		return 0;
+	}
+
+	if (gr == NULL)
+	{
+		gr = calloc(1, sizeof(graph));
+		if (!gr)
+			err(1, "Out of memory");
+		gr->name = filename;
+		gr->category = "";
+	}
+
+	if (strcmp(header, "general") == 0)
+	{
+		if (strcmp(name, "title") == 0)
+			gr->title = value;
+		else if (strcmp(name, "category") == 0)
+			gr->category = value;
+	}
+	else if (strcmp(header, "graph") == 0)
+	{
+		if (strcmp(name, "height") == 0)
+			gr->height = atoi(value);
+		else if (strcmp(name, "width") == 0)
+			gr->width = atoi(value);
+	}
+	else if (strcmp(header, "poll") == 0)
+	{
+		if (strcmp(name, "interval") == 0)
+			gr->interval = atoi(value);
+	}
+}
+
+int cfg_error(const char* filename, const char* errmsg, void* data)
+{
+	/* todo skip the rest of this file on error */
+    warnx("%s", errmsg);
+    return 0;
+}
+
+void
+freegraphs ()
+{
+	graph* l;
+	graph* t;
+
+	for (l = allgraphs; l != NULL; )
+	{
+		t = l->next;
+		free(l);
+		l = t;
+	}
+}
+
+/* -----------------------------------------------------------------------------
+ * METHODS
+ */
+
+static void
+listgraphs ()
+{
+	graph* l;
+
+	printf("Content-Type: text/xml\n\n");
+	printf("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
+	printf("<data>\n");
+
+	for (l = allgraphs; l != NULL; l = l->next)
+	{
+		printf("    <graph name=\"%s\" category=\"%s\" title=\"%s\"", \
+			  l->name, l->category, l->title);
+
+		if (l->width)
+			printf(" width=\"%d\"", l->width);
+
+		if (l->height)
+			printf(" height=\"%d\"", l->height);
+
+		if (l->interval)
+			printf(" interval=\"%d\"", l->interval);
+
+		printf(" />\n");
+	}
+	printf("</data>\n");
+}
+
+#if 0
+static void
+displaygraphs ()
+{
+	char* name = NULL;
+	int width;
+	int height;
+	char* q;
+	char* query = NULL;
+
+	q = getenv("QUERY_STRING");
+
+	if (q)
+	{
+		query = q = strdup(q);
+		while (q[0] && (q[0] == '?' || isspace(q[0])))
+			q++;
+
+		while (q && q[0])
+		{
+			nm = strsep(&q, "&");
+			vl = strchr(nm, '=');
+			if (!vl)
+				continue;
+			vl[0] = 0;
+			vl++;
+
+			if (strcmp(nm, "name") == 0)
+				name = vl;
+			else if (strcmp(nm, "width") == 0)
+				width = atoi(vl);
+			else if (strcmp(nm, "height") == )
+				height = atoi(vl);
+		}
+
+	}
+}
+#endif
+
+/* -----------------------------------------------------------------------------
+ * MAIN
+ */
+
+static void
+usererror (const char* msg)
+{
+	printf("Content-Type: text/plain\n\n");
+	printf("%s\n", msg);
+
+	/* Custom error so webserver doesn't think it's a server error */
+	exit(0);
+}
+
+static int
+pathstarts (const char* path, const char* method)
+{
+	int len = strlen(method);
+
+	if (strncmp(path, method, len) != 0)
+		return 0;
+
+	if (path[len] == '/' || !path[len])
+		return 1;
+
+	return 0;
+}
+
+int
+main (int argc, char* argv[])
+{
+	char* path;
+
+	conf_directory = getenv("CONFDIR");
+	work_directory = getenv("WORKDIR");
+
+	if (!conf_directory || !work_directory)
+		errx(2, "not setup properly. CONFDIR and WORKDIR env variables must be set");
+
+	/*
+	 * We always have this as our current directory.
+	 * It helps when constructing graphs and the like
+	 */
+	if (chdir(work_directory) < 0)
+		err(1, "Couldn't change to work directory: %s", work_directory);
+
+
+	path = getenv("PATH_INFO");
+
+	while (path && path[0] &&
+		   (isspace(path[0]) || path[0] == '/'))
+		path++;
+
+	cfg_parse_dir(conf_directory, NULL);
+
+	if (!path || !path[0] || pathstarts(path, "list"))
+		listgraphs();
+	else if (pathstarts(path, "graph"))
+		printf("graph\n");
+	else
+		usererror("Invalid request");
+
+	freegraphs();
+
+	return 0;
+}