Config file interpreter

3 files changed, 255 insertions, 0 deletions

diff --git a/FICS/build.mk b/FICS/build.mk
index 5c2e4f7..7355421 100644
--- a/FICS/build.mk
+++ b/FICS/build.mk
@@ -17,6 +17,7 @@ OBJS = $(SRC_DIR)adminproc.o\
 	$(SRC_DIR)formula.o\
 	$(SRC_DIR)gamedb.o\
 	$(SRC_DIR)gameproc.o\
+	$(SRC_DIR)interpreter.o\
 	$(SRC_DIR)iset.o\
 	$(SRC_DIR)legal.o\
 	$(SRC_DIR)legal2.o\
@@ -52,6 +53,7 @@ SRCS = $(SRC_DIR)adminproc.c\
 	$(SRC_DIR)formula.c\
 	$(SRC_DIR)gamedb.c\
 	$(SRC_DIR)gameproc.c\
+	$(SRC_DIR)interpreter.cpp\
 	$(SRC_DIR)iset.cpp\
 	$(SRC_DIR)legal.c\
 	$(SRC_DIR)legal2.c\
diff --git a/FICS/interpreter.cpp b/FICS/interpreter.cpp
new file mode 100644
index 0000000..4894c2f
--- /dev/null
+++ b/FICS/interpreter.cpp
@@ -0,0 +1,196 @@
+// SPDX-FileCopyrightText: 2012-2025 Markus Uhlin <maxxe@rpblc.net>
+// SPDX-License-Identifier: ISC
+
+#include <err.h>
+#include <errno.h>
+#include <iostream>
+#include <stdexcept>
+
+#include "interpreter.h"
+#include "utils.h"
+
+const char g_fgets_nullret_err1[70] = "error: fgets() returned null and the "
+    "error indicator is set";
+const char g_fgets_nullret_err2[70] = "error: fgets() returned null for an "
+    "unknown reason";
+
+static const char ArgBegin = '"';
+static const char ArgEnd = '"';
+static const char CommentChar = '#';
+
+static const size_t	identifier_maxSize = 64;
+static const size_t	argument_maxSize = 512;
+
+/**
+ * Copy identifier
+ */
+static char *
+copy_identifier(const char *&id)
+{
+	size_t	 count = identifier_maxSize;
+	char	*dest_buf = new char[count + 1];
+	char	*dest = &dest_buf[0];
+
+	while ((isalnum(*id) || *id == '_') && count > 1)
+		*dest++ = *id++, count--;
+
+	*dest = '\0';
+
+	if (count == 1)
+		errx(1, "%s: fatal: string was truncated", __func__);
+	return dest_buf;
+}
+
+/**
+ * Copy argument
+ */
+//lint -sem(copy_argument, r_null)
+static char *
+copy_argument(const char *&arg)
+{
+	bool	 inside_arg = true;
+	size_t	 count = argument_maxSize;
+	char	*dest_buf = new char[count + 1];
+	char	*dest = &dest_buf[0];
+
+	while (*arg && count > 1) {
+		if (*arg == ArgEnd) {
+			inside_arg = false;
+			arg++;
+			break;
+		}
+
+		*dest++ = *arg++, count--;
+	}
+
+	*dest = '\0';
+
+	if (inside_arg && count == 1)
+		errx(1, "%s: fatal: string was truncated", __func__);
+	if (inside_arg) {
+		delete[] dest_buf;
+		return nullptr;
+	}
+	return dest_buf;
+}
+
+static void
+clean_up(char *id, char *arg)
+{
+	delete[] id;
+	delete[] arg;
+}
+
+/**
+ * Interpreter
+ *
+ * @param in Context structure
+ * @return Void
+ *
+ * An interpreter for configuration files. The context structure
+ * contains the data to be passed to the interpreter.
+ */
+void
+Interpreter(const struct Interpreter_in *in)
+{
+	char	*id = nullptr;
+	char	*arg = nullptr;
+
+	if (in == nullptr)
+		errx(1, "%s: invalid argument", __func__);
+
+	try {
+		const char *cp = &in->line[0];
+
+		if (!isalnum(*cp) && *cp != '_')
+			throw std::runtime_error("unexpected leading "
+			    "character");
+		id = copy_identifier(cp);
+		adv_while_isspace(&cp);
+		if (*cp++ != '=') {
+			throw std::runtime_error("expected assignment "
+			    "operator");
+		}
+
+		adv_while_isspace(&cp);
+		if (*cp++ != ArgBegin)
+			throw std::runtime_error("expected arg begin");
+		else if ((arg = copy_argument(cp)) == nullptr)
+			throw std::runtime_error("unterminated argument");
+
+		adv_while_isspace(&cp);
+		if (*cp++ != ';')
+			throw std::runtime_error("no line terminator!");
+
+		adv_while_isspace(&cp);
+		if (*cp && *cp != CommentChar) {
+			throw std::runtime_error("implicit data after "
+			    "line terminator!");
+		} else if (!(in->validator_func(id))) {
+#if IGNORE_UNRECOGNIZED_IDENTIFIERS
+			/* ignore */;
+#else
+			throw std::runtime_error("no such identifier");
+#endif
+		} else if ((errno = in->install_func(id, arg)) != 0) {
+			throw std::runtime_error("install error");
+		}
+	} catch (const std::bad_alloc &e) {
+		std::cerr << "out of memory: " << e.what() << '\n';
+		clean_up(id, arg);
+		abort();
+	} catch (const std::runtime_error &e) {
+		std::cerr << '\t' << in->line << '\n';
+
+		if (strings_match(e.what(), "install error")) {
+			warn("%s:%ld: error: "
+			    "install_func returned %d", in->path, in->line_num,
+			    errno);
+		} else {
+			warnx("%s:%ld: error: %s", in->path, in->line_num,
+			    e.what());
+		}
+
+		clean_up(id, arg);
+		abort();
+	} catch (...) {
+		std::cerr << "unknown exception  --  should not be reached\n";
+		clean_up(id, arg);
+		abort();
+	}
+
+	clean_up(id, arg);
+}
+
+void
+Interpreter_processAllLines(FILE *fp, const char *path, Interpreter_vFunc func1,
+    Interpreter_instFunc func2)
+{
+	char		buf[MAXLINE] = { '\0' };
+	long int	line_num = 0;
+
+	while (fgets(buf, sizeof buf, fp) != nullptr) {
+		char			*line;
+		const char		*cp;
+		struct Interpreter_in	 in;
+
+		cp = &buf[0];
+		adv_while_isspace(&cp);
+		if (strings_match(cp, "") || *cp == CommentChar) {
+			line_num++;
+			continue;
+		}
+
+		if ((line = eattailwhite(xstrdup(cp))) == nullptr)
+			errx(1, "%s: unexpected null pointer", __func__);
+
+		in.path			= const_cast<char *>(path);
+		in.line			= line;
+		in.line_num		= ++line_num;
+		in.validator_func	= func1;
+		in.install_func		= func2;
+		Interpreter(&in);
+
+		free(line);
+	}
+}
diff --git a/FICS/interpreter.h b/FICS/interpreter.h
new file mode 100644
index 0000000..b807ad6
--- /dev/null
+++ b/FICS/interpreter.h
@@ -0,0 +1,57 @@
+#ifndef INTERPRETER_H
+#define INTERPRETER_H
+
+#include <ctype.h> /* isspace */
+#include <stdbool.h>
+#include <stdio.h> /* FILE */
+#include <string.h>
+
+#include "common.h"
+
+/*
+ * Set to 0 to turn off this feature.
+ */
+#define IGNORE_UNRECOGNIZED_IDENTIFIERS 1
+
+#define MAXLINE 3200
+
+enum setting_type {
+	TYPE_BOOLEAN,
+	TYPE_INTEGER,
+	TYPE_STRING
+};
+
+typedef bool (*Interpreter_vFunc)(const char *);
+typedef int (*Interpreter_instFunc)(const char *, const char *);
+
+struct Interpreter_in {
+	char *path;
+	char *line;
+	long int line_num;
+	Interpreter_vFunc validator_func;
+	Interpreter_instFunc install_func;
+};
+
+__FICS_BEGIN_DECLS
+extern const char g_fgets_nullret_err1[70];
+extern const char g_fgets_nullret_err2[70];
+
+void	Interpreter(const struct Interpreter_in *);
+void	Interpreter_processAllLines(FILE *, const char *, Interpreter_vFunc,
+	    Interpreter_instFunc);
+__FICS_END_DECLS
+
+static inline void
+adv_while_isspace(const char **ptr)
+{
+	while (isspace(**ptr))
+		(*ptr)++;
+}
+
+static inline bool
+strings_match(const char *str1, const char *str2)
+{
+	return (strcmp(str1, str2) == 0);
+}
+
+#endif