1 files changed, 107 insertions, 0 deletions
diff --git a/command/echo.c b/command/echo.c
new file mode 100644
index 0000000..a0ab78d
--- /dev/null
+++ b/command/echo.c
@@ -0,0 +1,107 @@
+#include "command.h"
+#include "lslib.h"
+
+#include <stdlib.h>
+
+static struct {
+    bool escape_codes;
+    bool newline;
+} flags;
+
+static void print_with_escape_codes(const char* str) {
+    
+    size_t index = 0;
+    char n;
+
+    while (true) {
+        char c = str[index];
+        index++;
+
+        if (c == '\0') break;
+        if (c != '\\') {
+            putchar(c);
+            continue;
+        }
+
+        n = str[index];
+        index++;
+
+        switch (n) {
+            case '\\':
+                putchar('\\');
+                break;
+            case 'b':
+                putchar('\b');
+                break;
+            case 'c':
+                exit(EXIT_SUCCESS);
+            case 'n':
+                putchar('\n');
+                break;
+            case 'r':
+                putchar('\r');
+                break;
+            case 't':
+                putchar('\t');
+                break;
+            case 'v':
+                putchar('\v');
+                break;
+            default:
+                putchar(c);
+                putchar(n);
+        }
+    }
+}
+
+static int short_arg(char c, char* next) {
+    UNUSED(next);
+    switch (c) {
+        case 'e':
+            flags.escape_codes = true;
+            break;
+        case 'E':
+            flags.escape_codes = false;
+            break;
+        case 'n':
+            flags.newline = false;
+            break;
+        default:
+            flags.newline = true;
+            flags.escape_codes = false;
+            return ARG_IGNORE;
+    };
+    return ARG_UNUSED;
+}
+
+COMMAND(echo) {
+
+    int start, i;
+
+    if (argc < 1) {
+        return EXIT_SUCCESS;
+    }
+
+    flags.escape_codes = false;
+    flags.newline = true;
+
+    start = parse_args(argc, argv, NULL, short_arg, NULL);
+
+    for (i = start; i < argc; i++) {
+         if (flags.escape_codes) {
+            print_with_escape_codes(argv[i]);
+        } else {
+            printf("%s", argv[i]);
+        }
+
+        if (i + 1 != argc) {
+            putchar(' ');
+        }
+    } 
+
+    if (flags.newline) {
+        putchar('\n');
+    }
+
+    return EXIT_SUCCESS;
+}