From fe4f42f090c18fe46708bc07e2d219ba066caf31 Mon Sep 17 00:00:00 2001
From: yuqing <yuqing@yongche.com>
Date: Fri, 25 Nov 2016 15:07:48 +0800
Subject: [PATCH] char_converter code refine

---
 src/char_converter.c | 76 ++++++++++++++++++++++++++++++++++++++++----
 src/char_converter.h | 34 ++++++++++++++++----
 2 files changed, 98 insertions(+), 12 deletions(-)

diff --git a/src/char_converter.c b/src/char_converter.c
index 41bab29..111acdc 100644
--- a/src/char_converter.c
+++ b/src/char_converter.c
@@ -33,7 +33,8 @@ int char_converter_init(FastCharConverter *pCharConverter,
     for (i=0; i<count; i++)
     {
         src = charPairs[i].src;
-        pCharConverter->char_table[src] = charPairs[i].dest;
+        pCharConverter->char_table[src].op = FAST_CHAR_OP_NO_BACKSLASH;
+        pCharConverter->char_table[src].dest = charPairs[i].dest;
     }
     return 0;
 }
@@ -63,15 +64,27 @@ int std_space_char_converter_init(FastCharConverter *pCharConverter,
 void char_converter_set_pair(FastCharConverter *pCharConverter,
         const unsigned char src, const unsigned char dest)
 {
-    pCharConverter->char_table[src] = dest;
+    char_converter_set_pair_ex(pCharConverter, src, FAST_CHAR_OP_NO_BACKSLASH, dest);
+}
+
+void char_converter_set_pair_ex(FastCharConverter *pCharConverter,
+        const unsigned char src, const unsigned op, const unsigned char dest)
+{
+    pCharConverter->char_table[src].op = op;
+    pCharConverter->char_table[src].dest = dest;
 }
 
 int fast_char_convert(FastCharConverter *pCharConverter,
-        char *text, const int text_len)
+        char *text, int *text_len, const int max_size)
 {
     int count;
     unsigned char *p;
+    unsigned char *pi;
     unsigned char *end;
+    char fixed_buff[16 * 1024];
+    char *buff;
+    int max_size_sub1;
+    int remain_len;
 
     if (pCharConverter->count <= 0)
     {
@@ -79,16 +92,67 @@ int fast_char_convert(FastCharConverter *pCharConverter,
     }
 
     count = 0;
-    end = (unsigned char *)text + text_len;
+    end = (unsigned char *)text + *text_len;
     for (p=(unsigned char *)text; p<end; p++)
     {
-        if (pCharConverter->char_table[*p] != 0)
+        if (pCharConverter->char_table[*p].op != FAST_CHAR_OP_NONE)
         {
-            *p = pCharConverter->char_table[*p];
+            if (pCharConverter->char_table[*p].op == FAST_CHAR_OP_ADD_BACKSLASH) {
+                break;
+            }
+
+            *p = pCharConverter->char_table[*p].dest;
             ++count;
         }
     }
 
+    remain_len = end - p;
+    if (remain_len == 0) {
+        return count;
+    }
+
+    if (remain_len < sizeof(fixed_buff)) {
+        buff = fixed_buff;
+    } else {
+        buff = (char *)malloc(remain_len);
+        if (buff == NULL) {
+            logError("file: "__FILE__", line: %d, "
+                    "malloc %d bytes fail", __LINE__, remain_len);
+            return count;
+        }
+    }
+    memcpy(buff, p, remain_len);
+
+    max_size_sub1 = max_size - 1;
+    end = (unsigned char *)buff + remain_len;
+    for (pi=(unsigned char *)buff; pi<end; pi++)
+    {
+        if (p - (unsigned char *)text >= max_size_sub1)
+        {
+            logWarning("file: "__FILE__", line: %d, "
+                    "exceeds max size: %d", __LINE__, max_size);
+            break;
+        }
+        if (pCharConverter->char_table[*pi].op != FAST_CHAR_OP_NONE)
+        {
+            if (pCharConverter->char_table[*pi].op == FAST_CHAR_OP_ADD_BACKSLASH)
+            {
+                *p++ = '\\';
+            }
+
+            *p++ = pCharConverter->char_table[*pi].dest;
+            ++count;
+        }
+        else
+        {
+            *p++ = *pi;
+        }
+    }
+
+    if (buff != fixed_buff) {
+        free(buff);
+    }
+    *text_len = p - (unsigned char *)text;
     return count;
 }
 
diff --git a/src/char_converter.h b/src/char_converter.h
index 206e82c..1cbfe04 100644
--- a/src/char_converter.h
+++ b/src/char_converter.h
@@ -20,12 +20,22 @@ extern "C" {
 
 #define FAST_MAX_CHAR_COUNT    256
 
+#define FAST_CHAR_OP_NONE           0
+#define FAST_CHAR_OP_ADD_BACKSLASH  1
+#define FAST_CHAR_OP_NO_BACKSLASH   2
+
 typedef struct fast_char_pair
 {
     unsigned char src;
     unsigned char dest;
 } FastCharPair;
 
+typedef struct fast_char_target
+{
+    unsigned char op;
+    unsigned char dest;
+} FastCharTarget;
+
 typedef struct fast_char_converter
 {
     /*
@@ -36,7 +46,7 @@ typedef struct fast_char_converter
     /*
      * char table to convert
      * */
-    unsigned char char_table[FAST_MAX_CHAR_COUNT];
+    FastCharTarget char_table[FAST_MAX_CHAR_COUNT];
 } FastCharConverter;
 
 /**
@@ -61,7 +71,7 @@ int std_space_char_converter_init(FastCharConverter *pCharConverter,
         const unsigned char dest_base);
 
 /**
- *  standard space chars to convert
+ *  set char pair to converter
  *  parameters:
  *           pCharConverter: the char converter
  *           src: the src char
@@ -71,17 +81,29 @@ int std_space_char_converter_init(FastCharConverter *pCharConverter,
 void char_converter_set_pair(FastCharConverter *pCharConverter,
         const unsigned char src, const unsigned char dest);
 
+/**
+ *  set char pair to converter
+ *  parameters:
+ *           pCharConverter: the char converter
+ *           src: the src char
+ *           op: the operator type
+ *           dest: the dest char
+ *  return: none
+*/
+void char_converter_set_pair_ex(FastCharConverter *pCharConverter,
+        const unsigned char src, const unsigned op, const unsigned char dest);
+
 /**
  *  char convert function
  *  parameters:
  *           pCharConverter: the char converter
- *           text: the text to convert
- *           text_len: the length of text
+ *           text: the text to convert (input and output)
+ *           text_len: the length of text (input and output)
+ *           max_size: max buff size
  *  return: converted char count
 */
 int fast_char_convert(FastCharConverter *pCharConverter,
-        char *text, const int text_len);
-
+        char *text, int *text_len, const int max_size);
 
 #ifdef __cplusplus
 }