(CHAR_HEAD_P): Take char, not pointer, as arg.

(INC_POS, DEC_POS): Fix because arg is a bufpos.
(BUF_INC_POS, BUF_DEC_POS): New macros.
(INC_BOTH, DEC_BOTH): New macros.

1 files changed, 59 insertions, 7 deletions

diff --git a/src/charset.h b/src/charset.h
index 2286e67e351..d2e500a83a7 100644
--- a/src/charset.h
+++ b/src/charset.h
@@ -134,9 +134,9 @@ extern int charset_latin_jisx0201; /* JISX0201.Roman (Japanese Roman) */
 extern int charset_big5_1;      /* Big5 Level 1 (Chinese Traditional) */
 extern int charset_big5_2;      /* Big5 Level 2 (Chinese Traditional) */
 
-/* Check if STR points the head of multi-byte form, i.e. *STR is an
-   ASCII character or a base leading-code.  */
-#define CHAR_HEAD_P(str) ((unsigned char) *(str) < 0xA0)
+/* Check if CH is the head of multi-byte form, i.e.,
+   an ASCII character or a base leading-code.  */
+#define CHAR_HEAD_P(ch) ((unsigned char) (ch) < 0xA0)
 
 /*** GENERAL NOTE on CHARACTER REPRESENTATION ***
 
@@ -599,10 +599,10 @@ extern int iso_charset_table[2][2][128];
    range checking of POS.  */
 #define INC_POS(pos)                            \
   do {                                          \
-    unsigned char *p = POS_ADDR (pos);          \
+    unsigned char *p = BYTE_POS_ADDR (pos);     \
     pos++;                                      \
     if (*p++ >= 0x80)                           \
-      while (!CHAR_HEAD_P (p)) p++, pos++;      \
+      while (!CHAR_HEAD_P (*p)) p++, pos++;     \
   } while (0)
 
 /* Decrease the buffer point POS of the current buffer to the previous
@@ -611,11 +611,63 @@ extern int iso_charset_table[2][2][128];
   do {                                                          \
     unsigned char *p, *p_min;                                   \
     int pos_saved = --pos;                                      \
-    if (pos < GPT)                                              \
+    if (pos < GPT_BYTE)                                         \
       p = BEG_ADDR + pos - 1, p_min = BEG_ADDR;                 \
     else                                                        \
       p = BEG_ADDR + GAP_SIZE + pos - 1, p_min = GAP_END_ADDR;  \
-    while (p > p_min && !CHAR_HEAD_P (p)) p--, pos--;           \
+    while (p > p_min && !CHAR_HEAD_P (*p)) p--, pos--;          \
+    if (*p < 0x80 && pos != pos_saved) pos = pos_saved;         \
+  } while (0)
+
+/* Increment both CHARPOS and BYTEPOS, each in the appropriate way.  */
+
+#define INC_BOTH(charpos, bytepos)              \
+do                                              \
+  {                                             \
+    (charpos)++;                                \
+    INC_POS ((bytepos));                        \
+  }                                             \
+while (0)
+
+/* Decrement both CHARPOS and BYTEPOS, each in the appropriate way.  */
+
+#define DEC_BOTH(charpos, bytepos)              \
+do                                              \
+  {                                             \
+    (charpos)--;                                \
+    DEC_POS ((bytepos));                        \
+  }                                             \
+while (0)
+
+/* Increase the buffer point POS of the current buffer to the next
+   character boundary.  This macro relies on the fact that *GPT_ADDR
+   and *Z_ADDR are always accessible and the values are '\0'.  No
+   range checking of POS.  */
+#define BUF_INC_POS(buf, pos)                   \
+  do {                                          \
+    unsigned char *p = BUF_BYTE_ADDRESS (buf, pos);     \
+    pos++;                                      \
+    if (*p++ >= 0x80)                           \
+      while (!CHAR_HEAD_P (*p)) p++, pos++;     \
+  } while (0)
+
+/* Decrease the buffer point POS of the current buffer to the previous
+   character boundary.  No range checking of POS.  */
+#define BUF_DEC_POS(buf, pos)                                   \
+  do {                                                          \
+    unsigned char *p, *p_min;                                   \
+    int pos_saved = --pos;                                      \
+    if (pos < BUF_GPT_BYTE (buf))                               \
+      {                                                         \
+        p = BUF_BEG_ADDR (buf) + pos - 1;                       \
+        p_min = BUF_BEG_ADDR (buf);                             \
+      }                                                         \
+    else                                                        \
+      {                                                         \
+        p = BUF_BEG_ADDR (buf) + BUF_GAP_SIZE (buf) + pos - 1;  \
+        p_min = BUF_GAP_END_ADDR (buf);                         \
+      }                                                         \
+    while (p > p_min && !CHAR_HEAD_P (*p)) p--, pos--;          \
     if (*p < 0x80 && pos != pos_saved) pos = pos_saved;         \
   } while (0)