zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/app/busybox/src/libbb/process_escape_sequence.c b/ap/app/busybox/src/libbb/process_escape_sequence.c
new file mode 100644
index 0000000..346ecfa
--- /dev/null
+++ b/ap/app/busybox/src/libbb/process_escape_sequence.c
@@ -0,0 +1,112 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) Manuel Novoa III <mjn3@codepoet.org>
+ * and Vladimir Oleynik <dzo@simtreas.ru>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+#include "libbb.h"
+
+#define WANT_HEX_ESCAPES 1
+
+/* Usual "this only works for ascii compatible encodings" disclaimer. */
+#undef _tolower
+#define _tolower(X) ((X)|((char) 0x20))
+
+char FAST_FUNC bb_process_escape_sequence(const char **ptr)
+{
+ const char *q;
+ unsigned num_digits;
+ unsigned n;
+ unsigned base;
+
+ num_digits = n = 0;
+ base = 8;
+ q = *ptr;
+
+ if (WANT_HEX_ESCAPES && *q == 'x') {
+ ++q;
+ base = 16;
+ ++num_digits;
+ }
+
+ /* bash requires leading 0 in octal escapes:
+ * \02 works, \2 does not (prints \ and 2).
+ * We treat \2 as a valid octal escape sequence. */
+ do {
+ unsigned r;
+#if !WANT_HEX_ESCAPES
+ unsigned d = (unsigned char)(*q) - '0';
+#else
+ unsigned d = (unsigned char)_tolower(*q) - '0';
+ if (d >= 10)
+ d += ('0' - 'a' + 10);
+#endif
+ if (d >= base) {
+ if (WANT_HEX_ESCAPES && base == 16) {
+ --num_digits;
+ if (num_digits == 0) {
+ /* \x<bad_char>: return '\',
+ * leave ptr pointing to x */
+ return '\\';
+ }
+ }
+ break;
+ }
+
+ r = n * base + d;
+ if (r > UCHAR_MAX) {
+ break;
+ }
+
+ n = r;
+ ++q;
+ } while (++num_digits < 3);
+
+ if (num_digits == 0) {
+ /* Not octal or hex escape sequence.
+ * Is it one-letter one? */
+
+ /* bash builtin "echo -e '\ec'" interprets \e as ESC,
+ * but coreutils "/bin/echo -e '\ec'" does not.
+ * Manpages tend to support coreutils way.
+ * Update: coreutils added support for \e on 28 Oct 2009. */
+ static const char charmap[] ALIGN1 = {
+ 'a', 'b', 'e', 'f', 'n', 'r', 't', 'v', '\\', '\0',
+ '\a', '\b', 27, '\f', '\n', '\r', '\t', '\v', '\\', '\\',
+ };
+ const char *p = charmap;
+ do {
+ if (*p == *q) {
+ q++;
+ break;
+ }
+ } while (*++p != '\0');
+ /* p points to found escape char or NUL,
+ * advance it and find what it translates to.
+ * Note that \NUL and unrecognized sequence \z return '\'
+ * and leave ptr pointing to NUL or z. */
+ n = p[sizeof(charmap) / 2];
+ }
+
+ *ptr = q;
+
+ return (char) n;
+}
+
+char* FAST_FUNC strcpy_and_process_escape_sequences(char *dst, const char *src)
+{
+ while (1) {
+ char c, c1;
+ c = c1 = *src++;
+ if (c1 == '\\')
+ c1 = bb_process_escape_sequence(&src);
+ *dst = c1;
+ if (c == '\0')
+ return dst;
+ dst++;
+ }
+}