add linenoise (#74)

examples/linenoise/CMakeLists.txt

@@ -0,0 +1,22 @@
+cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
+
+# ---- Dependencies ----
+
+include(../../cmake/CPM.cmake)
+
+CPMAddPackage(
+  NAME linenoise
+  GIT_TAG 1.0
+  GITHUB_REPOSITORY antirez/linenoise
+)
+
+if(linenoise_ADDED)
+  add_library(linenoise ${linenoise_SOURCE_DIR}/linenoise.c)
+  target_include_directories(linenoise PUBLIC ${linenoise_SOURCE_DIR})
+endif()
+
+# ---- Executable ----
+
+add_executable(CPMlinenoiseExample "main.cpp")
+set_target_properties(CPMlinenoiseExample PROPERTIES CXX_STANDARD 17)        
+target_link_libraries(CPMlinenoiseExample linenoise)

examples/linenoise/main.cpp

@@ -0,0 +1,64 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "linenoise.h"
+
+
+void completion(const char *buf, linenoiseCompletions *lc) {
+    if (buf[0] == 'h') {
+        linenoiseAddCompletion(lc,"hello");
+        linenoiseAddCompletion(lc,"hello there");
+    }
+}
+
+int main(int argc, char **argv) {
+    char *line;
+    char *prgname = argv[0];
+
+    /* Parse options, with --multiline we enable multi line editing. */
+    while(argc > 1) {
+        argc--;
+        argv++;
+        if (!strcmp(*argv,"--multiline")) {
+            linenoiseSetMultiLine(1);
+            printf("Multi-line mode enabled.\n");
+        } else if (!strcmp(*argv,"--keycodes")) {
+            linenoisePrintKeyCodes();
+            exit(0);
+        } else {
+            fprintf(stderr, "Usage: %s [--multiline] [--keycodes]\n", prgname);
+            exit(1);
+        }
+    }
+
+    /* Set the completion callback. This will be called every time the
+     * user uses the <tab> key. */
+    linenoiseSetCompletionCallback(completion);
+
+    /* Load history from file. The history file is just a plain text file
+     * where entries are separated by newlines. */
+    linenoiseHistoryLoad("history.txt"); /* Load the history at startup */
+
+    /* Now this is the main loop of the typical linenoise-based application.
+     * The call to linenoise() will block as long as the user types something
+     * and presses enter.
+     *
+     * The typed string is returned as a malloc() allocated string by
+     * linenoise, so the user needs to free() it. */
+    while((line = linenoise("hello> ")) != NULL) {
+        /* Do something with the string. */
+        if (line[0] != '\0' && line[0] != '/') {
+            printf("echo: '%s'\n", line);
+            linenoiseHistoryAdd(line); /* Add to the history. */
+            linenoiseHistorySave("history.txt"); /* Save the history on disk. */
+        } else if (!strncmp(line,"/historylen",11)) {
+            /* The "/historylen" command will change the history len. */
+            int len = atoi(line+11);
+            linenoiseHistorySetMaxLen(len);
+        } else if (line[0] == '/') {
+            printf("Unreconized command: %s\n", line);
+        }
+        free(line);
+    }
+    return 0;
+}