Move the escape-for-log code into src/lib/log

It doesn't need anything higher-level, and everything that needs the
logs potentially needs this.

src/common/util.c

@@ -559,128 +559,6 @@ tor_parse_uint64(const char *s, int base, uint64_t min,
   CHECK_STRTOX_RESULT();
 }
 
-/** Allocate and return a new string representing the contents of <b>s</b>,
- * surrounded by quotes and using standard C escapes.
- *
- * Generally, we use this for logging values that come in over the network to
- * keep them from tricking users, and for sending certain values to the
- * controller.
- *
- * We trust values from the resolver, OS, configuration file, and command line
- * to not be maliciously ill-formed.  We validate incoming routerdescs and
- * SOCKS requests and addresses from BEGIN cells as they're parsed;
- * afterwards, we trust them as non-malicious.
- */
-char *
-esc_for_log(const char *s)
-{
-  const char *cp;
-  char *result, *outp;
-  size_t len = 3;
-  if (!s) {
-    return tor_strdup("(null)");
-  }
-
-  for (cp = s; *cp; ++cp) {
-    switch (*cp) {
-      case '\\':
-      case '\"':
-      case '\'':
-      case '\r':
-      case '\n':
-      case '\t':
-        len += 2;
-        break;
-      default:
-        if (TOR_ISPRINT(*cp) && ((uint8_t)*cp)<127)
-          ++len;
-        else
-          len += 4;
-        break;
-    }
-  }
-
-  tor_assert(len <= SSIZE_MAX);
-
-  result = outp = tor_malloc(len);
-  *outp++ = '\"';
-  for (cp = s; *cp; ++cp) {
-    /* This assertion should always succeed, since we will write at least
-     * one char here, and two chars for closing quote and nul later */
-    tor_assert((outp-result) < (ssize_t)len-2);
-    switch (*cp) {
-      case '\\':
-      case '\"':
-      case '\'':
-        *outp++ = '\\';
-        *outp++ = *cp;
-        break;
-      case '\n':
-        *outp++ = '\\';
-        *outp++ = 'n';
-        break;
-      case '\t':
-        *outp++ = '\\';
-        *outp++ = 't';
-        break;
-      case '\r':
-        *outp++ = '\\';
-        *outp++ = 'r';
-        break;
-      default:
-        if (TOR_ISPRINT(*cp) && ((uint8_t)*cp)<127) {
-          *outp++ = *cp;
-        } else {
-          tor_assert((outp-result) < (ssize_t)len-4);
-          tor_snprintf(outp, 5, "\\%03o", (int)(uint8_t) *cp);
-          outp += 4;
-        }
-        break;
-    }
-  }
-
-  tor_assert((outp-result) <= (ssize_t)len-2);
-  *outp++ = '\"';
-  *outp++ = 0;
-
-  return result;
-}
-
-/** Similar to esc_for_log. Allocate and return a new string representing
- * the first n characters in <b>chars</b>, surround by quotes and using
- * standard C escapes. If a NUL character is encountered in <b>chars</b>,
- * the resulting string will be terminated there.
- */
-char *
-esc_for_log_len(const char *chars, size_t n)
-{
-  char *string = tor_strndup(chars, n);
-  char *string_escaped = esc_for_log(string);
-  tor_free(string);
-  return string_escaped;
-}
-
-/** Allocate and return a new string representing the contents of <b>s</b>,
- * surrounded by quotes and using standard C escapes.
- *
- * THIS FUNCTION IS NOT REENTRANT.  Don't call it from outside the main
- * thread.  Also, each call invalidates the last-returned value, so don't
- * try log_warn(LD_GENERAL, "%s %s", escaped(a), escaped(b));
- */
-const char *
-escaped(const char *s)
-{
-  static char *escaped_val_ = NULL;
-  tor_free(escaped_val_);
-
-  if (s)
-    escaped_val_ = esc_for_log(s);
-  else
-    escaped_val_ = NULL;
-
-  return escaped_val_;
-}
-
 /** Return a newly allocated string equal to <b>string</b>, except that every
  * character in <b>chars_to_escape</b> is preceded by a backslash. */
 char *

src/common/util.h

@@ -33,6 +33,7 @@
 #include "lib/intmath/cmp.h"
 #include "lib/log/ratelim.h"
 #include "lib/log/util_bug.h"
+#include "lib/log/escape.h"
 
 #ifndef O_BINARY
 #define O_BINARY 0
@@ -99,10 +100,6 @@ int tor_mem_is_zero(const char *mem, size_t len);
 int tor_digest_is_zero(const char *digest);
 int tor_digest256_is_zero(const char *digest);
 
-char *esc_for_log(const char *string) ATTR_MALLOC;
-char *esc_for_log_len(const char *chars, size_t n) ATTR_MALLOC;
-const char *escaped(const char *string);
-
 char *tor_escape_str_for_pt_args(const char *string,
                                  const char *chars_to_escape);
 

src/lib/log/escape.c

@@ -0,0 +1,132 @@
+/* Copyright (c) 2003, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#include "lib/log/escape.h"
+#include "lib/log/util_bug.h"
+#include "lib/string/compat_ctype.h"
+#include "lib/string/printf.h"
+#include "lib/malloc/util_malloc.h"
+
+/** Allocate and return a new string representing the contents of <b>s</b>,
+ * surrounded by quotes and using standard C escapes.
+ *
+ * Generally, we use this for logging values that come in over the network to
+ * keep them from tricking users, and for sending certain values to the
+ * controller.
+ *
+ * We trust values from the resolver, OS, configuration file, and command line
+ * to not be maliciously ill-formed.  We validate incoming routerdescs and
+ * SOCKS requests and addresses from BEGIN cells as they're parsed;
+ * afterwards, we trust them as non-malicious.
+ */
+char *
+esc_for_log(const char *s)
+{
+  const char *cp;
+  char *result, *outp;
+  size_t len = 3;
+  if (!s) {
+    return tor_strdup("(null)");
+  }
+
+  for (cp = s; *cp; ++cp) {
+    switch (*cp) {
+      case '\\':
+      case '\"':
+      case '\'':
+      case '\r':
+      case '\n':
+      case '\t':
+        len += 2;
+        break;
+      default:
+        if (TOR_ISPRINT(*cp) && ((uint8_t)*cp)<127)
+          ++len;
+        else
+          len += 4;
+        break;
+    }
+  }
+
+  tor_assert(len <= SSIZE_MAX);
+
+  result = outp = tor_malloc(len);
+  *outp++ = '\"';
+  for (cp = s; *cp; ++cp) {
+    /* This assertion should always succeed, since we will write at least
+     * one char here, and two chars for closing quote and nul later */
+    tor_assert((outp-result) < (ssize_t)len-2);
+    switch (*cp) {
+      case '\\':
+      case '\"':
+      case '\'':
+        *outp++ = '\\';
+        *outp++ = *cp;
+        break;
+      case '\n':
+        *outp++ = '\\';
+        *outp++ = 'n';
+        break;
+      case '\t':
+        *outp++ = '\\';
+        *outp++ = 't';
+        break;
+      case '\r':
+        *outp++ = '\\';
+        *outp++ = 'r';
+        break;
+      default:
+        if (TOR_ISPRINT(*cp) && ((uint8_t)*cp)<127) {
+          *outp++ = *cp;
+        } else {
+          tor_assert((outp-result) < (ssize_t)len-4);
+          tor_snprintf(outp, 5, "\\%03o", (int)(uint8_t) *cp);
+          outp += 4;
+        }
+        break;
+    }
+  }
+
+  tor_assert((outp-result) <= (ssize_t)len-2);
+  *outp++ = '\"';
+  *outp++ = 0;
+
+  return result;
+}
+
+/** Similar to esc_for_log. Allocate and return a new string representing
+ * the first n characters in <b>chars</b>, surround by quotes and using
+ * standard C escapes. If a NUL character is encountered in <b>chars</b>,
+ * the resulting string will be terminated there.
+ */
+char *
+esc_for_log_len(const char *chars, size_t n)
+{
+  char *string = tor_strndup(chars, n);
+  char *string_escaped = esc_for_log(string);
+  tor_free(string);
+  return string_escaped;
+}
+
+/** Allocate and return a new string representing the contents of <b>s</b>,
+ * surrounded by quotes and using standard C escapes.
+ *
+ * THIS FUNCTION IS NOT REENTRANT.  Don't call it from outside the main
+ * thread.  Also, each call invalidates the last-returned value, so don't
+ * try log_warn(LD_GENERAL, "%s %s", escaped(a), escaped(b));
+ */
+const char *
+escaped(const char *s)
+{
+  static char *escaped_val_ = NULL;
+  tor_free(escaped_val_);
+
+  if (s)
+    escaped_val_ = esc_for_log(s);
+  else
+    escaped_val_ = NULL;
+
+  return escaped_val_;
+}

src/lib/log/escape.h

@@ -0,0 +1,18 @@
+/* Copyright (c) 2001, Matej Pfajfar.
+ * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_ESCAPE_H
+#define TOR_ESCAPE_H
+
+#include "orconfig.h"
+#include "lib/cc/compat_compiler.h"
+#include <stddef.h>
+
+char *esc_for_log(const char *string) ATTR_MALLOC;
+char *esc_for_log_len(const char *chars, size_t n) ATTR_MALLOC;
+const char *escaped(const char *string);
+
+#endif /* !defined(TOR_TORLOG_H) */

src/lib/log/include.am

@@ -6,6 +6,7 @@ noinst_LIBRARIES += src/lib/libtor-log-testing.a
 endif
 
 src_lib_libtor_log_a_SOURCES =			\
+	src/lib/log/escape.c			\
 	src/lib/log/ratelim.c			\
 	src/lib/log/torlog.c			\
 	src/lib/log/util_bug.c
@@ -19,6 +20,7 @@ src/lib/log/torlog.$(OBJEXT) \
   src/lib/log/src_lib_libtor_log_testing_a-torlog.$(OBJEXT): micro-revision.i
 
 noinst_HEADERS +=					\
+	src/lib/log/escape.h				\
 	src/lib/log/ratelim.h				\
 	src/lib/log/torlog.h				\
 	src/lib/log/util_bug.h