Helps to "hg add" echo.c. Also, implement \0123 escapes for -e.

diff --git a/toys/echo.c b/toys/echo.c
new file mode 100644 (file)
index 0000000..93a3dbc
--- /dev/null
+++ b/toys/echo.c
@@ -0,0 +1,50 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * echo.c - echo supporting -n and -e.
+ */
+
+#include "toys.h"
+
+int echo_main(void)
+{
+       int i = 0;
+       char *arg, *from = "\\abfnrtv", *to = "\\\a\b\f\n\r\t\v";
+       
+       for (;;) {
+               arg = toys.optargs[i];
+               if (!arg) break;
+               if (i++) xputc(' ');
+               
+               if (toys.optflags&2) {
+                       int c, j = 0;
+                       for (;;) {
+                               c = arg[j++];
+                               if (!c) break;
+                               if (c == '\\') {
+                                       char *found;
+                                       int d = arg[j++];
+
+
+                                       if (d) {
+                                               found = strchr(from, d);
+                                               if (found) c = to[found-from];
+                                               else if (d == 'c') goto done;
+                                               else if (d == '0') {
+                                                       c = 0;
+                                                       while (arg[j]>='0' && arg[j]<='7')
+                                                               c = (c*8)+arg[j++]-'0';
+                                               }
+                                               // \0123
+                                       }
+                               }
+                               xputc(c);
+                       }
+                       // \\ thingy
+               } else xprintf("%s", arg);
+       }
+       // Output "\n" if no -n
+       if (!(toys.optflags&1)) xputc('\n');
+done:
+       xflush();
+       return 0;
+}