+#endif
+
+/* The syntax table cache */
+
+/*
+ The *-single-property-change versions turn out to be unbearably slow.
+ Do not enable them in a production or distribution version.
+*/
+#define NEXT_SINGLE_PROPERTY_CHANGE 0
+#define PREVIOUS_SINGLE_PROPERTY_CHANGE 0
+
+/* Test instruments, used in macros below.
+ Define SYNTAX_CACHE_STATISTICS to enable them. */
+/* #undef SYNTAX_CACHE_STATISTICS */
+
+#ifdef SYNTAX_CACHE_STATISTICS
+#define SYNTAX_CACHE_STATISTICS_REPORT_INTERVAL 100000
+
+enum syntax_cache_statistics_functions {
+ scs_no_function = -1,
+ scs_find_context = 0,
+ scs_find_defun_start,
+ scs_scan_words,
+ scs_Fforward_comment,
+ scs_scan_lists,
+ scs_Fbackward_prefix_characters,
+ scs_scan_sexps_forward,
+ scs_number_of_functions
+};
+
+/* keep this in synch with syntax.c */
+extern char* syntax_cache_statistics_function_names[scs_number_of_functions];
+
+struct syntax_cache_statistics {
+ /* inits + misses_hi + misses_lo + #HITS = total_updates */
+ int total_updates;
+ int inits;
+ int misses_lo;
+ int misses_hi;
+ int min_length;
+ int max_length;
+ double mean_length;
+ double mean_length_on_miss;
+ enum syntax_cache_statistics_functions this_function;
+ int functions[scs_number_of_functions];
+};
+
+extern struct syntax_cache_statistics scs_statistics;
+
+#define SCS_STATISTICS_SET_FUNCTION(fndx) scs_statistics.this_function = fndx
+/* used in macros below */
+#define SYNTAX_CACHE_STATISTICS_COUNT_INIT scs_statistics.inits++
+
+#else
+
+#define SCS_STATISTICS_SET_FUNCTION(fndx)
+#define SYNTAX_CACHE_STATISTICS_COUNT_INIT
+
+#endif /* SYNTAX_CACHE_STATISTICS */
+
+/* Theory of the syntax table cache
+
+ This cache cooperates with but is conceptually different from the
+ mirror table. The mirror table precomputes (and caches, if you like)
+ the syntax codes for characters in a given syntax table, taking into
+ account possible inheritance from a table given by a parent text object.
+ The syntax table cache checks for overriding tables defined by
+ _subobjects_.
+
+ This implementation defines the "subobjects" by _extent properties_.
+ We may restrict them to _text_ properties. There are two lookup
+ styles for the cache, "single code" and "full table". In the "single
+ code" style, a given syntax code, kept in the `syntax_code' member, is
+ applied to the entire range (#### check this). In the "full table"
+ style, a syntax table kept in the `current_syntax_table' member is
+ checked for each character in the range. If the flag `use_code' is
+ non-zero, the "single code" is used, otherwise the "full table".
+
+ The cache is valid for the range `[prev_change, next_change)' in the
+ text object (buffer or string) `object'.
+
+ If the current position is outside the range valid for the cache, the
+ cache is updated by checking for the text property `syntax-table'. If
+ present, its value is either a syntax code or a syntax table, and the
+ appropriate member and `use_code' are updated accordingly. If absent
+ or nil, the default syntax table from the `buffer' member is used. The
+ extent of the property is used to reinitialize the cache's validity
+ range. (We would like to improve this by checking the property value
+ against `old_prop', and if the same, extend the validity range of the
+ cache by the extent of the property.)
+
+ Note: the values Qt and Qnil for `object' are not supported in this
+ implementation. GNU Emacs uses them for reasons not yet (####) clear.
+*/
+
+extern int lookup_syntax_properties;
+
+struct syntax_cache
+{
+ int use_code; /* Whether to use syntax_code
+ or current_syntax_table. */
+ struct buffer* buffer; /* The buffer providing the default
+ syntax table to the cache. */
+ Lisp_Object object; /* The buffer or string the current
+ syntax cache applies to. */
+ enum syntaxcode syntax_code; /* Syntax code of current char. */
+ Lisp_Object current_syntax_table; /* Syntax table for current pos. */
+ Lisp_Object old_prop; /* Syntax-table prop at prev pos. */
+
+ Bufpos next_change; /* Position of the next extent
+ change. */
+ Bufpos prev_change; /* Position of the previous
+ extent change. */
+};
+extern struct syntax_cache syntax_cache;
+
+/*
+ The macros below handle the internal structure of the cache.
+ ALWAYS USE THE MACROS TO MANIPULATE THE CACHE.
+
+ o Use the SETUP_SYNTAX_CACHE* macros to set the object and buffer members.
+
+ OBJECT is either a Lisp buffer or a Lisp string. BUFFER is a
+ pointer to struct buffer. If OBJECT is a buffer, it must refer to
+ BUFFER. If OBJECT is a string, then BUFFER will supply the default
+ syntax table when the `syntax-table' property is nil.
+
+ For convenience and backward compatibility, the values Qt and Qnil are
+ accepted for OBJECT. These are taken to refer to the current buffer,
+ and that substitution is made immediately. The value Qt is treated
+ specially in the *BYTE_TO_CHAR macros below. This appears (####) to
+ be a GNU kludge related to `enable-multibyte-characters' and was used
+ only in dired.c.
+
+ FROM is the starting character position in OBJECT.
+ COUNT is currently used only as a flag. If positive, we are proceeding
+ forward through OBJECT, otherwise in reverse.
+
+ o All other members are updated using the update_syntax_cache
+ function, normally wrapped in the UPDATE_SYNTAX_CACHE* macros.
+*/
+
+void update_syntax_cache (int pos, int count);
+
+/* in one example the high misses vastly outweigh the low ones
+ seems plausible, since we typically are moving forward through the buffer */
+#define UPDATE_SYNTAX_CACHE_INTERNAL(pos, dir) \
+ ((lookup_syntax_properties && \
+ (pos >= syntax_cache.next_change || \
+ pos < syntax_cache.prev_change)) \
+ ? (update_syntax_cache ((pos), dir), 1) \
+ : 0)
+
+/* In the current implementation, all of the following are identical. */
+/* Make syntax cache state good for CHARPOS, assuming it is
+ currently good for a position before CHARPOS. */
+#define UPDATE_SYNTAX_CACHE_FORWARD(pos) UPDATE_SYNTAX_CACHE_INTERNAL(pos, 1)
+
+/* Make syntax cache state good for CHARPOS, assuming it is
+ currently good for a position after CHARPOS. */
+#define UPDATE_SYNTAX_CACHE_BACKWARD(pos) UPDATE_SYNTAX_CACHE_INTERNAL(pos, -1)
+
+/* Make syntax cache state good for CHARPOS */
+#define UPDATE_SYNTAX_CACHE(pos) UPDATE_SYNTAX_CACHE_INTERNAL(pos, 0)
+
+#define SYNTAX_FROM_CACHE(table, c) \
+ SYNTAX_FROM_CODE (SYNTAX_CODE_FROM_CACHE (table, c))
+
+#define SYNTAX_CODE_FROM_CACHE(table, c) \
+ ( syntax_cache.use_code \
+ ? syntax_cache.syntax_code \
+ : SYNTAX_CODE (XCHAR_TABLE (syntax_cache.current_syntax_table), \
+ c) \
+ )
+
+/* Convert the byte offset BYTEPOS into a character position,
+ for the object recorded in syntax_cache with SETUP_SYNTAX_CACHE*.
+
+ The value is meant for use in the UPDATE_SYNTAX_CACHE... macros.
+ These macros do nothing when lookup_syntax_properties is 0,
+ so we return 0 in that case, for speed.
+
+ The default case does no conversion; this seems (####) to be an
+ evil hangover from GNU Emacs. */
+#define SYNTAX_CACHE_OBJECT_BYTE_TO_CHAR(obj, buf, bytepos) \
+ (! lookup_syntax_properties \
+ ? 0 \
+ : STRINGP (obj) \
+ ? bytecount_to_charcount (XSTRING_DATA (obj), bytepos) \
+ : (BUFFERP (obj) || NILP (obj)) \
+ ? bytind_to_bufpos (buf, bytepos + BI_BUF_BEGV (buf)) \
+ : (bytepos))
+
+#define SYNTAX_CACHE_BYTE_TO_CHAR(bytepos) \
+ SYNTAX_CACHE_OBJECT_BYTE_TO_CHAR (syntax_cache.object, syntax_cache.buffer, \
+ (bytepos))
+
+#define SETUP_SYNTAX_CACHE(FROM, COUNT) \
+ SETUP_SYNTAX_CACHE_FOR_BUFFER (current_buffer, (FROM), (COUNT))
+
+#define SETUP_SYNTAX_CACHE_FOR_BUFFER(BUFFER, FROM, COUNT) \
+ SETUP_SYNTAX_CACHE_FOR_OBJECT (Qnil, (BUFFER), (FROM), (COUNT))
+
+#ifdef UTF2000
+#define SETUP_SYNTAX_CACHE_FOR_OBJECT(OBJECT, BUFFER, FROM, COUNT) \
+ do { \
+ syntax_cache.buffer = (BUFFER); \
+ syntax_cache.object = (OBJECT); \
+ if (NILP (syntax_cache.object)) \
+ { \
+ XSETBUFFER (syntax_cache.object, syntax_cache.buffer); \
+ } \
+ else if (EQ (syntax_cache.object, Qt)) \
+ { \
+ XSETBUFFER (syntax_cache.object, syntax_cache.buffer); \
+ } \
+ else if (STRINGP (syntax_cache.object)) \
+ { \
+ /* do nothing */; \
+ } \
+ else if (BUFFERP (syntax_cache.object)) \
+ { \
+ syntax_cache.buffer = XBUFFER (syntax_cache.object); \
+ } \
+ else \
+ { \
+ /* OBJECT must be buffer/string/t/nil */ \
+ assert(0); \
+ } \
+ syntax_cache.current_syntax_table \
+ = syntax_cache.buffer->syntax_table; \
+ syntax_cache.use_code = 0; \
+ if (lookup_syntax_properties) \
+ { \
+ SYNTAX_CACHE_STATISTICS_COUNT_INIT; \
+ update_syntax_cache ((FROM) + ((COUNT) > 0 ? 0 : -1), (COUNT)); \
+ } \
+ } while (0)
+#else
+#define SETUP_SYNTAX_CACHE_FOR_OBJECT(OBJECT, BUFFER, FROM, COUNT) \
+ do { \
+ syntax_cache.buffer = (BUFFER); \
+ syntax_cache.object = (OBJECT); \
+ if (NILP (syntax_cache.object)) \
+ { \
+ XSETBUFFER (syntax_cache.object, syntax_cache.buffer); \
+ } \
+ else if (EQ (syntax_cache.object, Qt)) \
+ { \
+ XSETBUFFER (syntax_cache.object, syntax_cache.buffer); \
+ } \
+ else if (STRINGP (syntax_cache.object)) \
+ { \
+ /* do nothing */; \
+ } \
+ else if (BUFFERP (syntax_cache.object)) \
+ { \
+ syntax_cache.buffer = XBUFFER (syntax_cache.object); \
+ } \
+ else \
+ { \
+ /* OBJECT must be buffer/string/t/nil */ \
+ assert(0); \
+ } \
+ syntax_cache.current_syntax_table \
+ = syntax_cache.buffer->mirror_syntax_table; \
+ syntax_cache.use_code = 0; \
+ if (lookup_syntax_properties) \
+ { \
+ SYNTAX_CACHE_STATISTICS_COUNT_INIT; \
+ update_syntax_cache ((FROM) + ((COUNT) > 0 ? 0 : -1), (COUNT)); \
+ } \
+ } while (0)
+#endif
+
+#define SYNTAX_CODE_PREFIX(c) \
+ ((c >> 7) & 1)
+
+#define SYNTAX_CODE_COMMENT_BITS(c) \
+ ((c >> 16) &0xff)
+
+#define SYNTAX_CODES_START_P(a, b) \
+ (((SYNTAX_CODE_COMMENT_BITS (a) & SYNTAX_FIRST_CHAR_START) >> 2) \
+ & (SYNTAX_CODE_COMMENT_BITS (b) & SYNTAX_SECOND_CHAR_START))
+
+#define SYNTAX_CODES_END_P(a, b) \
+ (((SYNTAX_CODE_COMMENT_BITS (a) & SYNTAX_FIRST_CHAR_END) >> 2) \
+ & (SYNTAX_CODE_COMMENT_BITS (b) & SYNTAX_SECOND_CHAR_END))
+
+#define SYNTAX_CODES_COMMENT_MASK_START(a, b) \
+ (SYNTAX_CODES_MATCH_START_P (a, b, SYNTAX_COMMENT_STYLE_A) \
+ ? SYNTAX_COMMENT_STYLE_A \
+ : (SYNTAX_CODES_MATCH_START_P (a, b, SYNTAX_COMMENT_STYLE_B) \
+ ? SYNTAX_COMMENT_STYLE_B \
+ : 0))
+#define SYNTAX_CODES_COMMENT_MASK_END(a, b) \
+ (SYNTAX_CODES_MATCH_END_P (a, b, SYNTAX_COMMENT_STYLE_A) \
+ ? SYNTAX_COMMENT_STYLE_A \
+ : (SYNTAX_CODES_MATCH_END_P (a, b, SYNTAX_COMMENT_STYLE_B) \
+ ? SYNTAX_COMMENT_STYLE_B \
+ : 0))
+
+#define SYNTAX_CODE_START_FIRST_P(a) \
+ (SYNTAX_CODE_COMMENT_BITS (a) & SYNTAX_FIRST_CHAR_START)
+
+#define SYNTAX_CODE_START_SECOND_P(a) \
+ (SYNTAX_CODE_COMMENT_BITS (a) & SYNTAX_SECOND_CHAR_START)
+
+#define SYNTAX_CODE_END_FIRST_P(a) \
+ (SYNTAX_CODE_COMMENT_BITS (a) & SYNTAX_FIRST_CHAR_END)
+
+#define SYNTAX_CODE_END_SECOND_P(a) \
+ (SYNTAX_CODE_COMMENT_BITS (a) & SYNTAX_SECOND_CHAR_END)
+
+
+#define SYNTAX_CODES_MATCH_START_P(a, b, mask) \
+ ((SYNTAX_CODE_COMMENT_BITS (a) & SYNTAX_FIRST_CHAR_START & (mask)) \
+ && (SYNTAX_CODE_COMMENT_BITS (b) & SYNTAX_SECOND_CHAR_START & (mask)))
+
+#define SYNTAX_CODES_MATCH_END_P(a, b, mask) \
+ ((SYNTAX_CODE_COMMENT_BITS (a) & SYNTAX_FIRST_CHAR_END & (mask)) \
+ && (SYNTAX_CODE_COMMENT_BITS (b) & SYNTAX_SECOND_CHAR_END & (mask)))
+
+#define SYNTAX_CODE_MATCHES_1CHAR_P(a, mask) \
+ ((SYNTAX_CODE_COMMENT_BITS (a) & (mask)))
+
+#define SYNTAX_CODE_COMMENT_1CHAR_MASK(a) \
+ ((SYNTAX_CODE_MATCHES_1CHAR_P (a, SYNTAX_COMMENT_STYLE_A) \
+ ? SYNTAX_COMMENT_STYLE_A \
+ : (SYNTAX_CODE_MATCHES_1CHAR_P (a, SYNTAX_COMMENT_STYLE_B) \
+ ? SYNTAX_COMMENT_STYLE_B \
+ : 0)))
+
+#if 0
+/* These are the things that need to be #defined away to create a
+ no syntax-table property version. */
+
+/* This should be entirely encapsulated in macros
+#define update_syntax_cache(pos, count)
+*/
+#define lookup_syntax_properties 0
+
+#define SETUP_SYNTAX_CACHE(FROM, COUNT)
+#define SETUP_SYNTAX_CACHE_FOR_BUFFER(BUFFER, FROM, COUNT)
+#define SETUP_SYNTAX_CACHE_FOR_OBJECT(OBJECT, BUFFER, FROM, COUNT)
+#define UPDATE_SYNTAX_CACHE_FORWARD(pos)
+#define UPDATE_SYNTAX_CACHE_BACKWARD(pos)
+#define UPDATE_SYNTAX_CACHE(pos)
+
+#define SYNTAX_FROM_CACHE SYNTAX
+#define SYNTAX_CODE_FROM_CACHE SYNTAX_CODE
+
+#define SYNTAX_CACHE_BYTE_TO_CHAR(x) 0
+
+/* cache statistics */
+#define SCS_STATISTICS_SET_FUNCTION(fndx)
+#define SYNTAX_CACHE_STATISTICS_COUNT_INIT