1 files changed, 130 insertions, 0 deletions
diff --git a/parser.c b/parser.c
new file mode 100644
index 0000000..87eb498
--- /dev/null
+++ b/parser.c
@@ -0,0 +1,130 @@
+#include "cccl.h"
+
+#include <assert.h>
+#include <err.h>
+#include <stddef.h>
+#include <stdlib.h>
+
+
+static enum cccl_NodeType get_nodetype(char c)
+{
+    switch (c)
+    {
+#define X(char, name) case char: return cccl_Node_##name
+        X('^', PUSHZERO);
+        X('+', INCREMENT);
+        X('-', DECREMENT);
+        X('*', ADD);
+        X('~', SUBTRACT);
+        X('%', REVERSE);
+        X('=', ASSIGN);
+        X('!', DELETE);
+        X('$', PUSHVAR);
+        X('&', ASSIGNLOCAL);
+        X('<', OUTPUT);
+        X('>', INPUT);
+        X('{', PROCEDURE);
+        X('}', PROCEDURE);
+        X('@', CALL);
+        X('(', INFINITE);
+        X(')', INFINITE);
+        X('[', REPEAT);
+        X(']', REPEAT);
+        X('#', END);
+        X(':', CONTINUE);
+        X('?', CONDITIONAL);
+        X(';', CONDITIONAL);
+#undef X
+    }
+    err(1, "Unrecognized command: [%d] %c", c, c);
+}
+
+
+struct cccl_Node *cccl_parse(struct cccl_Token tokens[], size_t tokens_length, enum cccl_NodeType type, char value)
+{
+    struct cccl_Node *res = malloc(sizeof(*res));
+    *res = (struct cccl_Node)
+    {
+        .type = type,
+        .in = NULL,
+        .in_length = 0,
+        .value = value,
+    };
+
+    for (size_t i = 0; i < tokens_length; ++i)
+    {
+        switch (tokens[i].type)
+        {
+        case cccl_Token_COMMAND: case cccl_Token_COMMANDWITHARG: case cccl_Token_BLOCKSTART:
+        {
+            if (!res->in)
+            {
+                res->in_length = 1;
+                res->in = malloc(sizeof(*res->in));
+            } else
+            {
+                ++res->in_length;
+                res->in = realloc(res->in, sizeof(*res->in) * res->in_length);
+            }
+        } break;
+        }
+
+        switch (tokens[i].type)
+        {
+        case cccl_Token_COMMAND:
+        {
+            res->in[res->in_length - 1] = malloc(sizeof(struct cccl_Node));
+            *res->in[res->in_length - 1] = (struct cccl_Node)
+            {
+                .type = get_nodetype(tokens[i].value),
+            };
+        } break;
+        case cccl_Token_COMMANDWITHARG:
+        {
+            assert(i + 1 != tokens_length);
+            res->in[res->in_length - 1] = malloc(sizeof(struct cccl_Node));
+            *res->in[res->in_length - 1] = (struct cccl_Node)
+            {
+                .type = get_nodetype(tokens[i].value),
+                .value = tokens[i + 1].value,
+            };
+        } break;
+        case cccl_Token_BLOCKSTART:
+        {
+            assert(i > 0);
+            char opening = tokens[i].value, closing;
+            switch (tokens[i].value)
+            {
+            break; case '{': closing = '}';
+            break; case '(': closing = ')';
+            break; case '[': closing = ']';
+            break; case '?': closing = ';';
+            }
+
+            size_t oldi = i;
+            int depth = 1;
+            for (; i < tokens_length; ++i)
+            {
+                if (tokens[i].value == opening)
+                    ++depth;
+                else if (tokens[i].value == closing)
+                    --depth;
+
+                if (depth == 0)
+                    goto end;
+            }
+            errx(1, "No matching bracket for %c", opening);
+
+end:
+            res->in[res->in_length - 1] = cccl_parse(
+                tokens + oldi + 1,
+                i - oldi - 1,
+                get_nodetype(tokens[i].value),
+                tokens[oldi - 1].value
+            );
+        } break;
+        }
+    }
+
+    return res;
+}