Add args

- --help
- --version

include/arg.h

@@ -2,6 +2,8 @@
 #define ARG_H
 #include <stdbool.h>
 
+#define LAT_VERSION "0.4.0"
+
 struct config {
   bool color;
   bool lines;

src/lib/arg.c

@@ -4,9 +4,25 @@
 #include <stdlib.h>
 #include <string.h>
 
+#define LAT_USAGE "usage: lat [cnVh] [files..]"
+
+void help(void) {
+  printf("%s\n", LAT_USAGE);
+  printf("options:\n"
+         "\t-c, --color\t toggle whether to print color or not\n"
+         "\t-n, --lines\t toggle whether to print line numbers or not\n"
+         "\t-V, --version\t show program version\n"
+         "\t-h, --help\t display this help text\n");
+}
+
+void version(void) {
+  printf("lat - v%s | %s:%s\n", LAT_VERSION, __DATE__, __TIME__);
+}
+
 struct config conf;
 void argerr(char *r, char *arg) {
-  fprintf(stderr, "lat: %s '%s'\n", r, arg);
+  printf("lat: %s '%s'\n", r, arg);
+  printf("%s\n", LAT_USAGE);
   exit(EXIT_FAILURE);
 }
 
@@ -21,6 +37,18 @@ void parselongarg(char *arg) {
     return;
   }
 
+  if (strcmp(arg, "--help") == 0) {
+    help();
+    exit(EXIT_SUCCESS);
+    return;
+  }
+
+  if (strcmp(arg, "--version") == 0) {
+    version();
+    exit(EXIT_SUCCESS);
+    return;
+  }
+
   argerr("unrecognized arg", arg);
 }
 
@@ -35,9 +63,22 @@ void parseshortarg(char *arg) {
     case 'n':
       conf.lines = !conf.lines;
       break;
-    default:
+    case 'h':
-      argerr("unrecognized flag", &c);
+      help();
+      exit(EXIT_SUCCESS);
       break;
+    case 'V':
+      version();
+      exit(EXIT_SUCCESS);
+      break;
+    default: {
+      char *str = malloc(2);
+      str[0] = c;
+      str[1] = '\0';
+      argerr("unrecognized flag", str);
+      free(str);
+      break;
+    }
     }
     i++;
   }

src/main.c

@@ -24,8 +24,8 @@ void run(FILE *fp, char *filename, int tty) {
 
   if (tty) {
     char *addon = f.binary ? "<binary>" : "";
-    fprintf(stderr, "\r%s%s%s%s\r\n", invert_t, basename(filename), addon,
+    fprintf(stderr, "\r\x1b[2K%s%s%s%s\r\n", invert_t, basename(filename),
-            uinvert_t);
+            addon, uinvert_t);
   }
 
   int lcpad = intlen(f.lc);
@@ -82,7 +82,7 @@ int main(int argc, char *argv[]) {
 
   if (argc > 1) {
     int offset = parseargs(argc, argv);
-    for (int i = offset; i < argc; i++) { // start at one to offset argv[0]
+    for (int i = offset; i < argc; i++) {
       FILE *fp = fopen(argv[i], "rb");
       if (fp == NULL)
         die(argv[i]);
@@ -91,10 +91,14 @@ int main(int argc, char *argv[]) {
       run(fp, argv[i], tty);
       fclose(fp);
 
-      if (i + 1 != argc) {
+      if (tty && (i + 1 != argc)) {
-        fprintf(stderr, "\r\n"); // separate concurrent files
+        fprintf(stderr, "\r\n"); // separate concurrent files in tty
       }
     }
+
+    if (offset == argc) {
+      run(stdin, "stdin", 1);
+    }
   } else {
     run(stdin, "stdin", 1); // for piped-input or repl-like behavior
   }