[ADD/WIP] Start working on basic parser header

src/include/Parser.h

@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2022-2023 Jordan Bancino <@jordan:bancino.net>
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#ifndef TELODENDRIA_PARSER_H
+#define TELODENDRIA_PARSER_H
+
+/***
+ * @Nm Parser
+ * @Nd Functions for dealing with simple grammars.
+ * @Dd November 24 2023
+ * @Xr User
+ *
+ * The
+ * .Nm
+ * API provides a simple parsing interface for basic parsers.
+ */
+
+/**
+ * A lot of functions here use this opaque structure.
+ */
+typedef struct Parser Parser;
+
+/**
+ * Create a new parser with an input string.
+ */
+extern Parser * ParserCreate(char *);
+
+/**
+ * Returns true if the character at the current position in 
+ * the parsing process is the one given in, and advances by 
+ * one character eitherway.
+ */
+extern int ParserExcept(Parser *, char);
+
+/**
+ * Starts a clipping session. This stores an index into the 
+ * parser, until 
+ * .Fn ParserEndCopy 
+ * is called.
+ */
+extern void ParserStartCopy(Parser *);
+/**
+ * Ends a clipping station created by 
+ * .Fn ParserStartCopy 
+ * if it was called beforehand into a new buffer to be freed 
+ * with
+ * .Fn Free .
+ */
+extern char * ParserEndCopy(Parser *);
+
+/**
+ * Frees a parser created with 
+ * .Fn ParserCreate .
+ */
+extern void ParserEnd(Parser *);
+#endif                             /* TELODENDRIA_PARSER_H */