From 58e0d435c38c0b4e6c59244436556dba6ed96abf Mon Sep 17 00:00:00 2001
From: Shav Kinderlehrer <shav@trinket.icu>
Date: Wed, 12 Apr 2023 23:46:53 -0400
Subject: [PATCH] Add args

- add color arg
- add lines arg
---
 include/arg.h  | 14 +++++++++++
 include/file.h |  4 ++--
 include/util.h |  1 +
 src/lib/arg.c  | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++
 src/lib/util.c |  2 +-
 src/main.c     | 24 +++++++++----------
 6 files changed, 94 insertions(+), 15 deletions(-)
 create mode 100644 include/arg.h
 create mode 100644 src/lib/arg.c

diff --git a/include/arg.h b/include/arg.h
new file mode 100644
index 0000000..be7ca0e
--- /dev/null
+++ b/include/arg.h
@@ -0,0 +1,14 @@
+#ifndef ARG_H
+#define ARG_H
+#include <stdbool.h>
+
+struct config {
+  bool color;
+  bool lines;
+};
+
+extern struct config conf;
+
+int parseargs(int argc, char *argv[]);
+
+#endif
diff --git a/include/file.h b/include/file.h
index 8dbaf86..df3b515 100644
--- a/include/file.h
+++ b/include/file.h
@@ -1,7 +1,7 @@
-#include <stdio.h>
-
 #ifndef FILE_H
 #define FILE_H
+
+#include <stdio.h>
 struct filedata {
   int lc;
   size_t len;
diff --git a/include/util.h b/include/util.h
index ddb86fc..1b0243c 100644
--- a/include/util.h
+++ b/include/util.h
@@ -1,5 +1,6 @@
 #ifndef LIB_H
 #define LIB_H
+#include <stdbool.h>
 #include <stddef.h>
 
 void die(const char *message);
diff --git a/src/lib/arg.c b/src/lib/arg.c
new file mode 100644
index 0000000..6178156
--- /dev/null
+++ b/src/lib/arg.c
@@ -0,0 +1,64 @@
+#include "arg.h"
+#include "util.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct config conf;
+void argerr(char *r, char *arg) {
+  fprintf(stderr, "lat: %s '%s'\n", r, arg);
+  exit(EXIT_FAILURE);
+}
+
+void parselongarg(char *arg) {
+  if (strcmp(arg, "--color") == 0) {
+    conf.color = !conf.color;
+    return;
+  }
+
+  if (strcmp(arg, "--lines") == 0) {
+    conf.lines = !conf.lines;
+    return;
+  }
+
+  argerr("unrecognized arg", arg);
+}
+
+void parseshortarg(char *arg) {
+  size_t i = 1;
+  while (arg[i] != '\0') {
+    char c = arg[i];
+    switch (c) {
+    case 'c':
+      conf.color = !conf.color;
+      break;
+    case 'n':
+      conf.lines = !conf.lines;
+      break;
+    default:
+      argerr("unrecognized flag", &c);
+      break;
+    }
+    i++;
+  }
+}
+
+int parseargs(int argc, char *argv[]) {
+  int i;
+  for (i = 1; i < argc; i++) { // offset for argv[0]
+    char *arg = argv[i];
+
+    if (arg[0] == '-') {
+      if (arg[1] == '-') {
+        parselongarg(arg);
+        continue;
+      }
+
+      parseshortarg(arg);
+    } else {
+      return i;
+    }
+  }
+
+  return i;
+}
diff --git a/src/lib/util.c b/src/lib/util.c
index d2d4f6a..d66579d 100644
--- a/src/lib/util.c
+++ b/src/lib/util.c
@@ -4,7 +4,7 @@
 
 void die(const char *message) {
   perror(message);
-  exit(1);
+  exit(EXIT_FAILURE);
 }
 
 char *formatbytes(size_t bytes, float *rounded) {
diff --git a/src/main.c b/src/main.c
index db1be8e..dc4d5f8 100644
--- a/src/main.c
+++ b/src/main.c
@@ -4,6 +4,7 @@
 #include <string.h>
 #include <unistd.h>
 
+#include "arg.h"
 #include "file.h"
 #include "util.h"
 
@@ -12,12 +13,6 @@
 #define GREY "\x1b[90m"
 #define RESET "\x1b[0m"
 
-struct config {
-  int color;
-};
-
-struct config conf;
-
 void run(FILE *fp, char *filename, int tty) {
   const char *invert_t = conf.color ? INVERT_T : "";
   const char *uinvert_t = conf.color ? UINVERT_T : "";
@@ -41,7 +36,7 @@ void run(FILE *fp, char *filename, int tty) {
   for (size_t i = 0; i < f.len; i++) {
     c = f.buf[i];
 
-    if (tty && !f.binary && (pc == '\n' || i == 0)) {
+    if ((conf.lines && tty && !f.binary) && (pc == '\n' || i == 0)) {
       f.lc++;
 
       int padlen = lcpad - intlen(f.lc);
@@ -70,24 +65,29 @@ void run(FILE *fp, char *filename, int tty) {
   }
 }
 
-void initconf(void) { conf.color = 1; }
+void initconf(void) {
+  conf.color = true;
+  conf.lines = true;
+}
 
 int main(int argc, char *argv[]) {
   initconf();
 
+  // init no_color first so that args take priority
   char *no_color = getenv("NO_COLOR");
 
   if (no_color != NULL && no_color[0] != '\0') {
-    conf.color = 0;
+    conf.color = false;
   }
 
   if (argc > 1) {
-    for (int i = 1; i < argc; i++) { // start at one to offset argv[0]
+    int offset = parseargs(argc, argv);
+    for (int i = offset; i < argc; i++) { // start at one to offset argv[0]
       FILE *fp = fopen(argv[i], "rb");
       if (fp == NULL)
         die(argv[i]);
 
-      int tty = isatty(STDOUT_FILENO);
+      bool tty = isatty(STDOUT_FILENO);
       run(fp, argv[i], tty);
       fclose(fp);
 
@@ -99,5 +99,5 @@ int main(int argc, char *argv[]) {
     run(stdin, "stdin", 1); // for piped-input or repl-like behavior
   }
 
-  return 0;
+  return EXIT_SUCCESS;
 }