Trying to make this work

src/Makefile

@@ -0,0 +1,17 @@
+CC=gcc
+all: test
+shortcodes.c: shortcodes.rl
+	ragel -G2 shortcodes.rl -o shortcodes.c
+tests.so: shortcodes.c tests.c
+	$(CC) -fPIC -shared -g -o $@ $^ -lbg -lcgreen
+clean:
+	rm -f shortcodes.c *.o *.so tests
+test: tests.so
+	cgreen-runner $^
+debug:
+	cgreen-debug tests.so
+%o: %c
+	$(CC) -g -c -o $@ $^
+shortcodes.a: shortcodes.o
+	ar rcs $@ $^
+.PHONY: test debug

src/shortcodes.h

@@ -0,0 +1,60 @@
+#pragma once
+
+// A chunk is a reference to a piece of string
+// from "start" relative to its start
+// and goes on for len characters.
+struct chunk
+{
+    unsigned int start;
+    unsigned int len;
+};
+typedef struct chunk chunk;
+
+// An error
+struct sc_error
+{
+    unsigned int position;
+    unsigned int code;
+};
+typedef struct sc_error sc_error;
+
+// Describes a parsed shortcode
+struct shortcode
+{
+    chunk whole;
+    chunk name;
+    chunk data;
+    char matching;
+    chunk argnames[100];
+    chunk argvals[100];
+    unsigned int argcount;
+};
+typedef struct shortcode shortcode;
+
+struct sc_result
+{
+    shortcode sc[100];
+    unsigned int sccount;
+    sc_error errors[10];
+    unsigned int errcount;
+};
+typedef struct sc_result sc_result;
+
+// Error codes
+
+/* You are closing the wrong shortcode.
+Example:
+
+{{% foo %}}  {{% /bar %}}
+*/
+#define ERR_MISMATCHED_CLOSING_TAG 1
+
+/* You are using mismatched brackets.
+Example:
+
+{{% foo >}}
+*/
+#define ERR_MISMATCHED_BRACKET 2
+
+
+sc_result parse(char *);

src/shortcodes.rl

@@ -0,0 +1,135 @@
+#include <string.h>
+#include "shortcodes.h"
+
+%%{
+  machine shortcode;
+
+  action mark {
+    mark = p;
+  }
+
+  spc = space*;
+  sep = space+;
+  path = (alnum | '/' )+;
+
+  name = (alpha+ path?)
+    > mark
+    %{ sc_list[c_sc].name.start = mark-start;
+       sc_list[c_sc].name.len = p-mark;
+       sc_list[c_sc].matching = 0;
+      };
+  argname = alpha+
+    > mark
+    % {
+      sc_list[c_sc].argnames[sc_list[c_sc].argcount].start = mark-start;
+      sc_list[c_sc].argnames[sc_list[c_sc].argcount].len = p-mark;
+    };
+  qvalue = ('"' [^"]* '"')
+    > mark
+    % {
+      sc_list[c_sc].argvals[sc_list[c_sc].argcount].start = mark-start+1;
+      sc_list[c_sc].argvals[sc_list[c_sc].argcount].len = p-mark-2;
+      sc_list[c_sc].argcount++;
+    };
+
+  value = alnum+
+    > mark
+    % {
+      sc_list[c_sc].argvals[sc_list[c_sc].argcount].start = mark-start;
+      sc_list[c_sc].argvals[sc_list[c_sc].argcount].len = p-mark;
+      sc_list[c_sc].argcount++;
+    };
+
+  arg = ((argname '=')? (value|qvalue));
+
+  start_p = ('{{%');
+  end_p = '%}}';
+
+  start_b = ('{{<');
+  end_b = '>}}';
+
+  content = spc name (sep arg)* spc;
+
+  start = start_p | start_b ;
+  end = end_p | end_b ;
+
+  mismatched = ((start_p content end_b) | (start_b content end_p)) 
+  @{
+    // Since it's mismatched, remove the name
+    sc_list[c_sc].name.start = 0;
+    sc_list[c_sc].name.len=0;
+    result.errors[result.errcount].position = p-start-2;
+    result.errors[result.errcount].code = ERR_MISMATCHED_BRACKET;
+    result.errcount++;
+  };
+
+  shortcode = ((start_p content end_p) | (start_b content end_b))
+  > {
+      sc_list[c_sc].whole.start = p-start-1;
+    }
+  @ {
+      sc_list[c_sc].whole.len = p-start-sc_list[c_sc].whole.start+1;
+      data_mark = p+1;
+      c_sc++;
+    };
+
+  closing_shortcode = (start spc '/' name spc end)
+  > {
+    // Starting a "closing" shortcode ( {{ /foo }}), 
+    // close data (if previous shortcode is opening)
+    // If previous shortcode was closing, then previous 
+    // text can't be data.
+    if (sc_list[c_sc-1].matching == 0) {
+      sc_list[c_sc-1].data.start = data_mark-start;
+      sc_list[c_sc-1].data.len = p-data_mark-1;
+    }
+  };
+
+  matched_shortcode = (shortcode any* closing_shortcode)
+  @ {
+    if (
+        sc_list[c_sc-1].name.len != sc_list[c_sc].name.len ||
+        strncmp(
+          start + sc_list[c_sc-1].name.start,
+          start + sc_list[c_sc].name.start,
+          sc_list[c_sc-1].name.len) !=0) 
+    {
+      result.errors[result.errcount].position = 
+          sc_list[c_sc].whole.start;
+      result.errors[result.errcount].code = ERR_MISMATCHED_CLOSING_TAG;
+      result.errcount++;
+    } else {
+      // The previous shortcode is matching (mark it)
+      sc_list[c_sc-1].matching = 1;
+      sc_list[c_sc-1].whole.len = p-start-sc_list[c_sc-1].whole.start + 1;
+    }
+    // Do NOT increase c_sc
+};
+
+  main := (any* (shortcode | matched_shortcode | mismatched))*;
+}%%
+
+
+sc_result parse(char *input) {
+
+  %%write data;
+  char *eof, *ts, *te = 0;
+  int cs, act = 0;
+
+  char *start = input;
+  char *p = input;
+  char *pe = p + strlen(input);
+
+  sc_result result;
+  shortcode *sc_list = result.sc; 
+  int c_sc = 0;
+
+  char *mark = p;
+  char *data_mark = p;
+
+  %% write init;
+  %% write exec;
+
+  result.sccount = c_sc;
+  return result;
+}