From: Pavel Charvat <pavel.charvat@netcentrum.cz>
Date: Mon, 24 Apr 2006 11:56:13 +0000 (+0200)
Subject: Simple parser for escape sequences.
X-Git-Tag: holmes-import~645^2~11^2~56
X-Git-Url: http://mj.ucw.cz/gitweb/?a=commitdiff_plain;h=feb4a9d0c53a92e8880bc973363150b894224006;p=libucw.git

Simple parser for escape sequences.
---

diff --git a/lib/Makefile b/lib/Makefile
index e4126c7f..216da3c1 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -26,7 +26,8 @@ LIBUCW_MODS= \
 	md5 md5hex \
 	base64 base224 \
 	sync \
-	qache
+	qache \
+	string
 
 LIBUCW_INCLUDES= \
 	lib.h config.h math.h \
diff --git a/lib/lib.h b/lib/lib.h
index 06a42ece..9f7f59d4 100644
--- a/lib/lib.h
+++ b/lib/lib.h
@@ -250,4 +250,8 @@ struct sigaction;
 void handle_signal(int signum, struct sigaction *oldact);
 void unhandle_signal(int signum, struct sigaction *oldact);
 
+/* string.c */
+
+byte *str_unesc(byte *dest, byte *src);
+
 #endif
diff --git a/lib/stkstring.h b/lib/stkstring.h
index 8f58aec7..22808cc7 100644
--- a/lib/stkstring.h
+++ b/lib/stkstring.h
@@ -18,6 +18,7 @@
 #define stk_strarraycat(s,n) ({ char **_s=(s); int _n=(n); char *_x=alloca(stk_array_len(_s,_n)); stk_array_copy(_x, _s, _n); _x; })
 #define stk_printf(f...) ({ uns _l=stk_printf_internal(f); char *_x=alloca(_l); memcpy(_x, stk_printf_buf, _l); _x; })
 #define stk_hexdump(s,n) ({ uns _n=(n); char *_x=alloca(3*_n+1); stk_hexdump_internal(_x,(byte*)(s),_n); _x; })
+#define stk_str_unesc(s) ({ byte *_s=(s); byte *_d=alloca(strlen(_s)+1); str_unesc(_d, _s); _d; })
 
 uns stk_array_len(char **s, uns cnt);
 void stk_array_copy(char *x, char **s, uns cnt);
diff --git a/lib/string.c b/lib/string.c
new file mode 100644
index 00000000..01685f82
--- /dev/null
+++ b/lib/string.c
@@ -0,0 +1,66 @@
+/*
+ *	UCW Library -- String Routines
+ *
+ *	(c) 2006 Pavel Charvat <pchar@ucw.cz>
+ *
+ *	This software may be freely distributed and used according to the terms
+ *	of the GNU Lesser General Public License.
+ */
+
+#include "lib/lib.h"
+#include "lib/chartype.h"
+
+/* Expands C99-like escape sequences.
+ * It is safe to use the same buffer for both input and output. */
+byte *
+str_unesc(byte *d, byte *s)
+{
+  while (*s)
+    {
+      if (*s == '\\')
+	switch (s[1])
+	  {
+	    case 'a': *d++ = '\a'; s += 2; break;
+	    case 'b': *d++ = '\b'; s += 2; break;
+	    case 'f': *d++ = '\f'; s += 2; break;
+	    case 'n': *d++ = '\n'; s += 2; break;
+	    case 'r': *d++ = '\r'; s += 2; break;
+	    case 't': *d++ = '\t'; s += 2; break;
+	    case 'v': *d++ = '\v'; s += 2; break;
+	    case '\?': *d++ = '\?'; s += 2; break;
+	    case '\'': *d++ = '\''; s += 2; break;
+	    case '\"': *d++ = '\"'; s += 2; break;
+	    case '\\': *d++ = '\\'; s += 2; break;
+	    case '0':
+	      if (s[2] < '0' || s[2] > '7')
+		*d++ = *s++;
+	      else
+	        {
+		  uns v = 0;
+		  for (s += 2; *s >= '0' && *s <= '7' && v < 32; s++)
+		    v = (v << 3) + *s - '0';
+		  *d++ = v;
+		}
+	      break;
+	    case 'x':
+	      if (!Cxdigit(s[2]))
+		*d++ = *s++;
+	      else
+	        {
+		  uns v = 0;
+		  for (s += 2; Cxdigit(*s) && v < 16; s++)
+		    v = (v << 4) + (Cdigit(*s) ? (*s - '0') : ((*s | 32) - 'A' + 10));
+		  *d++ = v;
+		}
+	      break;
+            default:
+	      *d++ = *s++;
+	      break;
+	  }
+      else
+	*d++ = *s++;
+    }
+  *d = 0;
+  return d;
+}
+