better repl input, using linenoise

CMakeLists.txt

@@ -16,7 +16,7 @@ set_property(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} PROPERTY VS_STARTUP_PROJECT c
 include(FetchContent)
 
 file(GLOB sources CONFIGURE_DEPENDS ${PROJECT_SOURCE_DIR}/src/*.c)
-add_executable(${PROJECT_NAME} main.c)
+add_executable(${PROJECT_NAME} main.c ${PROJECT_SOURCE_DIR}/util/linenoise.c)
 target_sources(${PROJECT_NAME} PRIVATE ${sources})
 
 IF (NOT WIN32)

Makefile

@@ -21,6 +21,7 @@ CHDR=\
 	src/cbaselib.h\
 	src/cdump.h\
 	src/cundump.h\
+	util/linenoise.h\
 
 CSRC=\
 	src/cchunk.c\
@@ -37,6 +38,7 @@ CSRC=\
 	src/cbaselib.c\
 	src/cdump.c\
 	src/cundump.c\
+	util/linenoise.c\
 	main.c\
 
 COBJ=$(CSRC:.c=.o)

main.c

@@ -8,6 +8,8 @@
 #include "cundump.h"
 #include "cvm.h"
 
+#include "util/linenoise.h"
+
 #include <stdio.h>
 #include <stdlib.h>
 #ifdef _WIN32
@@ -63,7 +65,7 @@ static bool interpret(CState *state, const char *script, const char *mod)
 
 static void repl(CState *state)
 {
-    char line[1024];
+    char *line;
     _ACTIVE = true;
 
     // add our custom REPL functions
@@ -76,14 +78,13 @@ static void repl(CState *state)
     cosmoV_register(state, 2);
 
     while (_ACTIVE) {
-        printf("> ");
+        if (!(line = linenoise("> "))) { // better than gets()
-
-        if (!fgets(line, sizeof(line), stdin)) { // better than gets()
-            printf("\n> ");
             break;
         }
 
+        linenoiseHistoryAdd(line);
         interpret(state, line, "REPL");
+        linenoiseFree(line);
     }
 }
 

util/linenoise.h

@@ -0,0 +1,113 @@
+/* linenoise.h -- VERSION 1.0
+ *
+ * Guerrilla line editing library against the idea that a line editing lib
+ * needs to be 20,000 lines of C code.
+ *
+ * See linenoise.c for more information.
+ *
+ * ------------------------------------------------------------------------
+ *
+ * Copyright (c) 2010-2023, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *  *  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *
+ *  *  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __LINENOISE_H
+#define __LINENOISE_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h> /* For size_t. */
+
+extern char *linenoiseEditMore;
+
+/* The linenoiseState structure represents the state during line editing.
+ * We pass this state to functions implementing specific editing
+ * functionalities. */
+struct linenoiseState {
+    int in_completion;  /* The user pressed TAB and we are now in completion
+                         * mode, so input is handled by completeLine(). */
+    size_t completion_idx; /* Index of next completion to propose. */
+    int ifd;            /* Terminal stdin file descriptor. */
+    int ofd;            /* Terminal stdout file descriptor. */
+    char *buf;          /* Edited line buffer. */
+    size_t buflen;      /* Edited line buffer size. */
+    const char *prompt; /* Prompt to display. */
+    size_t plen;        /* Prompt length. */
+    size_t pos;         /* Current cursor position. */
+    size_t oldpos;      /* Previous refresh cursor position. */
+    size_t len;         /* Current edited line length. */
+    size_t cols;        /* Number of columns in terminal. */
+    size_t oldrows;     /* Rows used by last refrehsed line (multiline mode) */
+    int history_index;  /* The history index we are currently editing. */
+};
+
+typedef struct linenoiseCompletions {
+  size_t len;
+  char **cvec;
+} linenoiseCompletions;
+
+/* Non blocking API. */
+int linenoiseEditStart(struct linenoiseState *l, int stdin_fd, int stdout_fd, char *buf, size_t buflen, const char *prompt);
+char *linenoiseEditFeed(struct linenoiseState *l);
+void linenoiseEditStop(struct linenoiseState *l);
+void linenoiseHide(struct linenoiseState *l);
+void linenoiseShow(struct linenoiseState *l);
+
+/* Blocking API. */
+char *linenoise(const char *prompt);
+void linenoiseFree(void *ptr);
+
+/* Completion API. */
+typedef void(linenoiseCompletionCallback)(const char *, linenoiseCompletions *);
+typedef char*(linenoiseHintsCallback)(const char *, int *color, int *bold);
+typedef void(linenoiseFreeHintsCallback)(void *);
+void linenoiseSetCompletionCallback(linenoiseCompletionCallback *);
+void linenoiseSetHintsCallback(linenoiseHintsCallback *);
+void linenoiseSetFreeHintsCallback(linenoiseFreeHintsCallback *);
+void linenoiseAddCompletion(linenoiseCompletions *, const char *);
+
+/* History API. */
+int linenoiseHistoryAdd(const char *line);
+int linenoiseHistorySetMaxLen(int len);
+int linenoiseHistorySave(const char *filename);
+int linenoiseHistoryLoad(const char *filename);
+
+/* Other utilities. */
+void linenoiseClearScreen(void);
+void linenoiseSetMultiLine(int ml);
+void linenoisePrintKeyCodes(void);
+void linenoiseMaskModeEnable(void);
+void linenoiseMaskModeDisable(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LINENOISE_H */