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December 8, 2008 02:04
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/* | |
$Id: strscan.c 11708 2007-02-12 23:01:19Z shyouhei $ | |
Copyright (c) 1999-2006 Minero Aoki | |
This program is free software. | |
You can distribute/modify this program under the terms of | |
the Ruby License. For details, see the file COPYING. | |
*/ | |
#include "ruby.h" | |
#include "re.h" | |
#define STRSCAN_VERSION "0.7.0" | |
/* ======================================================================= | |
Data Type Definitions | |
======================================================================= */ | |
static VALUE StringScanner; | |
static VALUE ScanError; | |
struct strscanner | |
{ | |
/* multi-purpose flags */ | |
unsigned long flags; | |
#define FLAG_MATCHED (1 << 0) | |
/* the string to scan */ | |
VALUE str; | |
/* scan pointers */ | |
long prev; /* legal only when MATCHED_P(s) */ | |
long curr; /* always legal */ | |
/* the regexp register; legal only when MATCHED_P(s) */ | |
struct re_registers regs; | |
}; | |
#define MATCHED_P(s) ((s)->flags & FLAG_MATCHED) | |
#define MATCHED(s) (s)->flags |= FLAG_MATCHED | |
#define CLEAR_MATCH_STATUS(s) (s)->flags &= ~FLAG_MATCHED | |
#define S_PBEG(s) (RSTRING((s)->str)->ptr) | |
#define S_LEN(s) (RSTRING((s)->str)->len) | |
#define S_PEND(s) (S_PBEG(s) + S_LEN(s)) | |
#define CURPTR(s) (S_PBEG(s) + (s)->curr) | |
#define S_RESTLEN(s) (S_LEN(s) - (s)->curr) | |
#define EOS_P(s) ((s)->curr >= RSTRING(p->str)->len) | |
#define GET_SCANNER(obj,var) do {\ | |
Data_Get_Struct(obj, struct strscanner, var);\ | |
if (NIL_P(var->str)) rb_raise(rb_eArgError, "uninitialized StringScanner object");\ | |
} while (0) | |
/* ======================================================================= | |
Function Prototypes | |
======================================================================= */ | |
static VALUE infect _((VALUE str, struct strscanner *p)); | |
static VALUE extract_range _((struct strscanner *p, long beg_i, long end_i)); | |
static VALUE extract_beg_len _((struct strscanner *p, long beg_i, long len)); | |
static void check_strscan _((VALUE obj)); | |
static void strscan_mark _((struct strscanner *p)); | |
static void strscan_free _((struct strscanner *p)); | |
static VALUE strscan_s_allocate _((VALUE klass)); | |
static VALUE strscan_initialize _((int argc, VALUE *argv, VALUE self)); | |
static VALUE strscan_init_copy _((VALUE vself, VALUE vorig)); | |
static VALUE strscan_s_mustc _((VALUE self)); | |
static VALUE strscan_terminate _((VALUE self)); | |
static VALUE strscan_clear _((VALUE self)); | |
static VALUE strscan_get_string _((VALUE self)); | |
static VALUE strscan_set_string _((VALUE self, VALUE str)); | |
static VALUE strscan_concat _((VALUE self, VALUE str)); | |
static VALUE strscan_get_pos _((VALUE self)); | |
static VALUE strscan_set_pos _((VALUE self, VALUE pos)); | |
static VALUE strscan_do_scan _((VALUE self, VALUE regex, | |
int succptr, int getstr, int headonly)); | |
static VALUE strscan_scan _((VALUE self, VALUE re)); | |
static VALUE strscan_match_p _((VALUE self, VALUE re)); | |
static VALUE strscan_skip _((VALUE self, VALUE re)); | |
static VALUE strscan_check _((VALUE self, VALUE re)); | |
static VALUE strscan_scan_full _((VALUE self, VALUE re, | |
VALUE succp, VALUE getp)); | |
static VALUE strscan_scan_until _((VALUE self, VALUE re)); | |
static VALUE strscan_skip_until _((VALUE self, VALUE re)); | |
static VALUE strscan_check_until _((VALUE self, VALUE re)); | |
static VALUE strscan_search_full _((VALUE self, VALUE re, | |
VALUE succp, VALUE getp)); | |
static void adjust_registers_to_matched _((struct strscanner *p)); | |
static VALUE strscan_getch _((VALUE self)); | |
static VALUE strscan_get_byte _((VALUE self)); | |
static VALUE strscan_getbyte _((VALUE self)); | |
static VALUE strscan_peek _((VALUE self, VALUE len)); | |
static VALUE strscan_peep _((VALUE self, VALUE len)); | |
static VALUE strscan_unscan _((VALUE self)); | |
static VALUE strscan_bol_p _((VALUE self)); | |
static VALUE strscan_eos_p _((VALUE self)); | |
static VALUE strscan_empty_p _((VALUE self)); | |
static VALUE strscan_rest_p _((VALUE self)); | |
static VALUE strscan_matched_p _((VALUE self)); | |
static VALUE strscan_matched _((VALUE self)); | |
static VALUE strscan_matched_size _((VALUE self)); | |
static VALUE strscan_aref _((VALUE self, VALUE idx)); | |
static VALUE strscan_pre_match _((VALUE self)); | |
static VALUE strscan_post_match _((VALUE self)); | |
static VALUE strscan_rest _((VALUE self)); | |
static VALUE strscan_rest_size _((VALUE self)); | |
static VALUE strscan_inspect _((VALUE self)); | |
static VALUE inspect1 _((struct strscanner *p)); | |
static VALUE inspect2 _((struct strscanner *p)); | |
/* ======================================================================= | |
Utils | |
======================================================================= */ | |
static VALUE | |
infect(VALUE str, struct strscanner *p) | |
{ | |
OBJ_INFECT(str, p->str); | |
return str; | |
} | |
static VALUE | |
extract_range(struct strscanner *p, long beg_i, long end_i) | |
{ | |
if (beg_i > S_LEN(p)) return Qnil; | |
if (end_i > S_LEN(p)) | |
end_i = S_LEN(p); | |
return infect(rb_str_new(S_PBEG(p) + beg_i, end_i - beg_i), p); | |
} | |
static VALUE | |
extract_beg_len(struct strscanner *p, long beg_i, long len) | |
{ | |
if (beg_i > S_LEN(p)) return Qnil; | |
if (beg_i + len > S_LEN(p)) | |
len = S_LEN(p) - beg_i; | |
return infect(rb_str_new(S_PBEG(p) + beg_i, len), p); | |
} | |
/* ======================================================================= | |
Constructor | |
======================================================================= */ | |
static void | |
strscan_mark(struct strscanner *p) | |
{ | |
rb_gc_mark(p->str); | |
} | |
static void | |
strscan_free(struct strscanner *p) | |
{ | |
re_free_registers(&(p->regs)); | |
free(p); | |
} | |
static VALUE | |
strscan_s_allocate(VALUE klass) | |
{ | |
struct strscanner *p; | |
p = ALLOC(struct strscanner); | |
MEMZERO(p, struct strscanner, 1); | |
CLEAR_MATCH_STATUS(p); | |
MEMZERO(&(p->regs), struct re_registers, 1); | |
p->str = Qnil; | |
return Data_Wrap_Struct(klass, strscan_mark, strscan_free, p); | |
} | |
/* | |
* call-seq: StringScanner.new(string, dup = false) | |
* | |
* Creates a new StringScanner object to scan over the given +string+. | |
* +dup+ argument is obsolete and not used now. | |
*/ | |
static VALUE | |
strscan_initialize(int argc, VALUE *argv, VALUE self) | |
{ | |
struct strscanner *p; | |
VALUE str, need_dup; | |
Data_Get_Struct(self, struct strscanner, p); | |
rb_scan_args(argc, argv, "11", &str, &need_dup); | |
StringValue(str); | |
p->str = str; | |
return self; | |
} | |
static void | |
check_strscan(VALUE obj) | |
{ | |
if (TYPE(obj) != T_DATA || RDATA(obj)->dmark != (RUBY_DATA_FUNC)strscan_mark) { | |
rb_raise(rb_eTypeError, | |
"wrong argument type %s (expected StringScanner)", | |
rb_obj_classname(obj)); | |
} | |
} | |
/* | |
* call-seq: | |
* dup | |
* clone | |
* | |
* Duplicates a StringScanner object. | |
*/ | |
static VALUE | |
strscan_init_copy(VALUE vself, VALUE vorig) | |
{ | |
struct strscanner *self, *orig; | |
Data_Get_Struct(vself, struct strscanner, self); | |
check_strscan(vorig); | |
Data_Get_Struct(vorig, struct strscanner, orig); | |
if (self != orig) { | |
self->flags = orig->flags; | |
self->str = orig->str; | |
self->prev = orig->prev; | |
self->curr = orig->curr; | |
re_copy_registers(&self->regs, &orig->regs); | |
} | |
return vself; | |
} | |
/* ======================================================================= | |
Instance Methods | |
======================================================================= */ | |
/* | |
* call-seq: StringScanner.must_C_version | |
* | |
* This method is defined for backward compatibility. | |
*/ | |
static VALUE | |
strscan_s_mustc(VALUE self) | |
{ | |
return self; | |
} | |
/* | |
* Reset the scan pointer (index 0) and clear matching data. | |
*/ | |
static VALUE | |
strscan_reset(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
p->curr = 0; | |
CLEAR_MATCH_STATUS(p); | |
return self; | |
} | |
/* | |
* call-seq: | |
* terminate | |
* clear | |
* | |
* Set the scan pointer to the end of the string and clear matching data. | |
*/ | |
static VALUE | |
strscan_terminate(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
p->curr = S_LEN(p); | |
CLEAR_MATCH_STATUS(p); | |
return self; | |
} | |
/* | |
* Equivalent to #terminate. | |
* This method is obsolete; use #terminate instead. | |
*/ | |
static VALUE | |
strscan_clear(VALUE self) | |
{ | |
rb_warning("StringScanner#clear is obsolete; use #terminate instead"); | |
return strscan_terminate(self); | |
} | |
/* | |
* Returns the string being scanned. | |
*/ | |
static VALUE | |
strscan_get_string(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
return p->str; | |
} | |
/* | |
* call-seq: string=(str) | |
* | |
* Changes the string being scanned to +str+ and resets the scanner. | |
* Returns +str+. | |
*/ | |
static VALUE | |
strscan_set_string(VALUE self, VALUE str) | |
{ | |
struct strscanner *p; | |
Data_Get_Struct(self, struct strscanner, p); | |
StringValue(str); | |
p->str = rb_str_dup(str); | |
rb_obj_freeze(p->str); | |
p->curr = 0; | |
CLEAR_MATCH_STATUS(p); | |
return str; | |
} | |
/* | |
* call-seq: | |
* concat(str) | |
* <<(str) | |
* | |
* Appends +str+ to the string being scanned. | |
* This method does not affect scan pointer. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.scan(/Fri /) | |
* s << " +1000 GMT" | |
* s.string # -> "Fri Dec 12 1975 14:39 +1000 GMT" | |
* s.scan(/Dec/) # -> "Dec" | |
*/ | |
static VALUE | |
strscan_concat(VALUE self, VALUE str) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
StringValue(str); | |
rb_str_append(p->str, str); | |
return self; | |
} | |
/* | |
* Returns the position of the scan pointer. In the 'reset' position, this | |
* value is zero. In the 'terminated' position (i.e. the string is exhausted), | |
* this value is the length of the string. | |
* | |
* In short, it's a 0-based index into the string. | |
* | |
* s = StringScanner.new('test string') | |
* s.pos # -> 0 | |
* s.scan_until /str/ # -> "test str" | |
* s.pos # -> 8 | |
* s.terminate # -> #<StringScanner fin> | |
* s.pos # -> 11 | |
*/ | |
static VALUE | |
strscan_get_pos(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
return INT2FIX(p->curr); | |
} | |
/* | |
* call-seq: pos=(n) | |
* | |
* Modify the scan pointer. | |
* | |
* s = StringScanner.new('test string') | |
* s.pos = 7 # -> 7 | |
* s.rest # -> "ring" | |
*/ | |
static VALUE | |
strscan_set_pos(VALUE self, VALUE v) | |
{ | |
struct strscanner *p; | |
long i; | |
GET_SCANNER(self, p); | |
i = NUM2INT(v); | |
if (i < 0) i += S_LEN(p); | |
if (i < 0) rb_raise(rb_eRangeError, "index out of range"); | |
if (i > S_LEN(p)) rb_raise(rb_eRangeError, "index out of range"); | |
p->curr = i; | |
return INT2NUM(i); | |
} | |
static VALUE | |
strscan_do_scan(VALUE self, VALUE regex, int succptr, int getstr, int headonly) | |
{ | |
struct strscanner *p; | |
int ret; | |
Check_Type(regex, T_REGEXP); | |
GET_SCANNER(self, p); | |
CLEAR_MATCH_STATUS(p); | |
if (S_RESTLEN(p) < 0) { | |
return Qnil; | |
} | |
rb_kcode_set_option(regex); | |
if (headonly) { | |
ret = re_match(RREGEXP(regex)->ptr, | |
CURPTR(p), S_RESTLEN(p), | |
0, | |
&(p->regs)); | |
} | |
else { | |
ret = re_search(RREGEXP(regex)->ptr, | |
CURPTR(p), S_RESTLEN(p), | |
0, | |
S_RESTLEN(p), | |
&(p->regs)); | |
} | |
rb_kcode_reset_option(); | |
if (ret == -2) rb_raise(ScanError, "regexp buffer overflow"); | |
if (ret < 0) { | |
/* not matched */ | |
return Qnil; | |
} | |
MATCHED(p); | |
p->prev = p->curr; | |
if (succptr) { | |
p->curr += p->regs.end[0]; | |
} | |
if (getstr) { | |
return extract_beg_len(p, p->prev, p->regs.end[0]); | |
} | |
else { | |
return INT2FIX(p->regs.end[0]); | |
} | |
} | |
/* | |
* call-seq: scan(pattern) => String | |
* | |
* Tries to match with +pattern+ at the current position. If there's a match, | |
* the scanner advances the "scan pointer" and returns the matched string. | |
* Otherwise, the scanner returns +nil+. | |
* | |
* s = StringScanner.new('test string') | |
* p s.scan(/\w+/) # -> "test" | |
* p s.scan(/\w+/) # -> nil | |
* p s.scan(/\s+/) # -> " " | |
* p s.scan(/\w+/) # -> "string" | |
* p s.scan(/./) # -> nil | |
* | |
*/ | |
static VALUE | |
strscan_scan(VALUE self, VALUE re) | |
{ | |
return strscan_do_scan(self, re, 1, 1, 1); | |
} | |
/* | |
* call-seq: match?(pattern) | |
* | |
* Tests whether the given +pattern+ is matched from the current scan pointer. | |
* Returns the length of the match, or +nil+. The scan pointer is not advanced. | |
* | |
* s = StringScanner.new('test string') | |
* p s.match?(/\w+/) # -> 4 | |
* p s.match?(/\w+/) # -> 4 | |
* p s.match?(/\s+/) # -> nil | |
*/ | |
static VALUE | |
strscan_match_p(VALUE self, VALUE re) | |
{ | |
return strscan_do_scan(self, re, 0, 0, 1); | |
} | |
/* | |
* call-seq: skip(pattern) | |
* | |
* Attempts to skip over the given +pattern+ beginning with the scan pointer. | |
* If it matches, the scan pointer is advanced to the end of the match, and the | |
* length of the match is returned. Otherwise, +nil+ is returned. | |
* | |
* It's similar to #scan, but without returning the matched string. | |
* | |
* s = StringScanner.new('test string') | |
* p s.skip(/\w+/) # -> 4 | |
* p s.skip(/\w+/) # -> nil | |
* p s.skip(/\s+/) # -> 1 | |
* p s.skip(/\w+/) # -> 6 | |
* p s.skip(/./) # -> nil | |
* | |
*/ | |
static VALUE | |
strscan_skip(VALUE self, VALUE re) | |
{ | |
return strscan_do_scan(self, re, 1, 0, 1); | |
} | |
/* | |
* call-seq: check(pattern) | |
* | |
* This returns the value that #scan would return, without advancing the scan | |
* pointer. The match register is affected, though. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.check /Fri/ # -> "Fri" | |
* s.pos # -> 0 | |
* s.matched # -> "Fri" | |
* s.check /12/ # -> nil | |
* s.matched # -> nil | |
* | |
* Mnemonic: it "checks" to see whether a #scan will return a value. | |
*/ | |
static VALUE | |
strscan_check(VALUE self, VALUE re) | |
{ | |
return strscan_do_scan(self, re, 0, 1, 1); | |
} | |
/* | |
* call-seq: scan_full(pattern, return_string_p, advance_pointer_p) | |
* | |
* Tests whether the given +pattern+ is matched from the current scan pointer. | |
* Returns the matched string if +return_string_p+ is true. | |
* Advances the scan pointer if +advance_pointer_p+ is true. | |
* The match register is affected. | |
* | |
* "full" means "#scan with full parameters". | |
*/ | |
static VALUE | |
strscan_scan_full(VALUE self, VALUE re, VALUE s, VALUE f) | |
{ | |
return strscan_do_scan(self, re, RTEST(s), RTEST(f), 1); | |
} | |
/* | |
* call-seq: scan_until(pattern) | |
* | |
* Scans the string _until_ the +pattern+ is matched. Returns the substring up | |
* to and including the end of the match, advancing the scan pointer to that | |
* location. If there is no match, +nil+ is returned. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.scan_until(/1/) # -> "Fri Dec 1" | |
* s.pre_match # -> "Fri Dec " | |
* s.scan_until(/XYZ/) # -> nil | |
*/ | |
static VALUE | |
strscan_scan_until(VALUE self, VALUE re) | |
{ | |
return strscan_do_scan(self, re, 1, 1, 0); | |
} | |
/* | |
* call-seq: exist?(pattern) | |
* | |
* Looks _ahead_ to see if the +pattern+ exists _anywhere_ in the string, | |
* without advancing the scan pointer. This predicates whether a #scan_until | |
* will return a value. | |
* | |
* s = StringScanner.new('test string') | |
* s.exist? /s/ # -> 3 | |
* s.scan /test/ # -> "test" | |
* s.exist? /s/ # -> 6 | |
* s.exist? /e/ # -> nil | |
*/ | |
static VALUE | |
strscan_exist_p(VALUE self, VALUE re) | |
{ | |
return strscan_do_scan(self, re, 0, 0, 0); | |
} | |
/* | |
* call-seq: skip_until(pattern) | |
* | |
* Advances the scan pointer until +pattern+ is matched and consumed. Returns | |
* the number of bytes advanced, or +nil+ if no match was found. | |
* | |
* Look ahead to match +pattern+, and advance the scan pointer to the _end_ | |
* of the match. Return the number of characters advanced, or +nil+ if the | |
* match was unsuccessful. | |
* | |
* It's similar to #scan_until, but without returning the intervening string. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.skip_until /12/ # -> 10 | |
* s # | |
*/ | |
static VALUE | |
strscan_skip_until(VALUE self, VALUE re) | |
{ | |
return strscan_do_scan(self, re, 1, 0, 0); | |
} | |
/* | |
* call-seq: check_until(pattern) | |
* | |
* This returns the value that #scan_until would return, without advancing the | |
* scan pointer. The match register is affected, though. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.check_until /12/ # -> "Fri Dec 12" | |
* s.pos # -> 0 | |
* s.matched # -> 12 | |
* | |
* Mnemonic: it "checks" to see whether a #scan_until will return a value. | |
*/ | |
static VALUE | |
strscan_check_until(VALUE self, VALUE re) | |
{ | |
return strscan_do_scan(self, re, 0, 1, 0); | |
} | |
/* | |
* call-seq: search_full(pattern, return_string_p, advance_pointer_p) | |
* | |
* Scans the string _until_ the +pattern+ is matched. | |
* Returns the matched string if +return_string_p+ is true, otherwise | |
* returns the number of bytes advanced. | |
* Advances the scan pointer if +advance_pointer_p+, otherwise not. | |
* This method does affect the match register. | |
*/ | |
static VALUE | |
strscan_search_full(VALUE self, VALUE re, VALUE s, VALUE f) | |
{ | |
return strscan_do_scan(self, re, RTEST(s), RTEST(f), 0); | |
} | |
/* DANGEROUS; need to synchronize with regex.c */ | |
static void | |
adjust_registers_to_matched(struct strscanner *p) | |
{ | |
if (p->regs.allocated == 0) { | |
p->regs.beg = ALLOC_N(int, RE_NREGS); | |
p->regs.end = ALLOC_N(int, RE_NREGS); | |
p->regs.allocated = RE_NREGS; | |
} | |
p->regs.num_regs = 1; | |
p->regs.beg[0] = 0; | |
p->regs.end[0] = p->curr - p->prev; | |
} | |
/* | |
* Scans one character and returns it. | |
* This method is multi-byte character sensitive. | |
* See also #get_byte. | |
* | |
* s = StringScanner.new('ab') | |
* s.getch # => "a" | |
* s.getch # => "b" | |
* s.getch # => nil | |
* | |
* $KCODE = 'EUC' | |
* s = StringScanner.new("\244\242") | |
* s.getch # => "\244\242" # Japanese hira-kana "A" in EUC-JP | |
* s.getch # => nil | |
*/ | |
static VALUE | |
strscan_getch(VALUE self) | |
{ | |
struct strscanner *p; | |
long len; | |
GET_SCANNER(self, p); | |
CLEAR_MATCH_STATUS(p); | |
if (EOS_P(p)) | |
return Qnil; | |
len = mbclen(*CURPTR(p)); | |
if (p->curr + len > S_LEN(p)) { | |
len = S_LEN(p) - p->curr; | |
} | |
p->prev = p->curr; | |
p->curr += len; | |
MATCHED(p); | |
adjust_registers_to_matched(p); | |
return extract_range(p, p->prev + p->regs.beg[0], | |
p->prev + p->regs.end[0]); | |
} | |
/* | |
* Scans one byte and returns it. | |
* This method is NOT multi-byte character sensitive. | |
* See also #getch. | |
* | |
* s = StringScanner.new('ab') | |
* s.get_byte # => "a" | |
* s.get_byte # => "b" | |
* s.get_byte # => nil | |
* | |
* s = StringScanner.new("\244\242") | |
* s.get_byte # => "\244" | |
* s.get_byte # => "\242" | |
* s.get_byte # => nil | |
*/ | |
static VALUE | |
strscan_get_byte(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
CLEAR_MATCH_STATUS(p); | |
if (EOS_P(p)) { | |
return Qnil; | |
} | |
p->prev = p->curr; | |
p->curr++; | |
MATCHED(p); | |
adjust_registers_to_matched(p); | |
return extract_range(p, p->prev + p->regs.beg[0], | |
p->prev + p->regs.end[0]); | |
} | |
/* | |
* Equivalent to #get_byte. | |
* This method is obsolete; use #get_byte instead. | |
*/ | |
static VALUE | |
strscan_getbyte(VALUE self) | |
{ | |
rb_warning("StringScanner#getbyte is obsolete; use #get_byte instead"); | |
return strscan_get_byte(self); | |
} | |
/* | |
* call-seq: peek(len) | |
* | |
* Extracts a string corresponding to <tt>string[pos,len]</tt>, without | |
* advancing the scan pointer. | |
* | |
* s = StringScanner.new('test string') | |
* s.peek(7) # => "test st" | |
* s.peek(7) # => "test st" | |
* | |
*/ | |
static VALUE | |
strscan_peek(VALUE self, VALUE vlen) | |
{ | |
struct strscanner *p; | |
long len; | |
GET_SCANNER(self, p); | |
len = NUM2LONG(vlen); | |
if (EOS_P(p)) { | |
return infect(rb_str_new("", 0), p); | |
} | |
if (p->curr + len > S_LEN(p)) { | |
len = S_LEN(p) - p->curr; | |
} | |
return extract_beg_len(p, p->curr, len); | |
} | |
/* | |
* Equivalent to #peek. | |
* This method is obsolete; use #peek instead. | |
*/ | |
static VALUE | |
strscan_peep(VALUE self, VALUE vlen) | |
{ | |
rb_warning("StringScanner#peep is obsolete; use #peek instead"); | |
return strscan_peek(self, vlen); | |
} | |
/* | |
* Set the scan pointer to the previous position. Only one previous position is | |
* remembered, and it changes with each scanning operation. | |
* | |
* s = StringScanner.new('test string') | |
* s.scan(/\w+/) # => "test" | |
* s.unscan | |
* s.scan(/../) # => "te" | |
* s.scan(/\d/) # => nil | |
* s.unscan # ScanError: unscan failed: previous match had failed | |
*/ | |
static VALUE | |
strscan_unscan(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) { | |
rb_raise(ScanError, "unscan failed: previous match had failed"); | |
} | |
p->curr = p->prev; | |
CLEAR_MATCH_STATUS(p); | |
return self; | |
} | |
/* | |
* Returns +true+ iff the scan pointer is at the beginning of the line. | |
* | |
* s = StringScanner.new("test\ntest\n") | |
* s.bol? # => true | |
* s.scan(/te/) | |
* s.bol? # => false | |
* s.scan(/st\n/) | |
* s.bol? # => true | |
* s.terminate | |
* s.bol? # => true | |
*/ | |
static VALUE | |
strscan_bol_p(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (CURPTR(p) > S_PEND(p)) return Qnil; | |
if (p->curr == 0) return Qtrue; | |
return (*(CURPTR(p) - 1) == '\n') ? Qtrue : Qfalse; | |
} | |
/* | |
* Returns +true+ if the scan pointer is at the end of the string. | |
* | |
* s = StringScanner.new('test string') | |
* p s.eos? # => false | |
* s.scan(/test/) | |
* p s.eos? # => false | |
* s.terminate | |
* p s.eos? # => true | |
*/ | |
static VALUE | |
strscan_eos_p(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
return EOS_P(p) ? Qtrue : Qfalse; | |
} | |
/* | |
* Equivalent to #eos?. | |
* This method is obsolete, use #eos? instead. | |
*/ | |
static VALUE | |
strscan_empty_p(VALUE self) | |
{ | |
rb_warning("StringScanner#empty? is obsolete; use #eos? instead"); | |
return strscan_eos_p(self); | |
} | |
/* | |
* Returns true iff there is more data in the string. See #eos?. | |
* This method is obsolete; use #eos? instead. | |
* | |
* s = StringScanner.new('test string') | |
* s.eos? # These two | |
* s.rest? # are opposites. | |
*/ | |
static VALUE | |
strscan_rest_p(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
return EOS_P(p) ? Qfalse : Qtrue; | |
} | |
/* | |
* Returns +true+ iff the last match was successful. | |
* | |
* s = StringScanner.new('test string') | |
* s.match?(/\w+/) # => 4 | |
* s.matched? # => true | |
* s.match?(/\d+/) # => nil | |
* s.matched? # => false | |
*/ | |
static VALUE | |
strscan_matched_p(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
return MATCHED_P(p) ? Qtrue : Qfalse; | |
} | |
/* | |
* Returns the last matched string. | |
* | |
* s = StringScanner.new('test string') | |
* s.match?(/\w+/) # -> 4 | |
* s.matched # -> "test" | |
*/ | |
static VALUE | |
strscan_matched(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) return Qnil; | |
return extract_range(p, p->prev + p->regs.beg[0], | |
p->prev + p->regs.end[0]); | |
} | |
/* | |
* Returns the size of the most recent match (see #matched), or +nil+ if there | |
* was no recent match. | |
* | |
* s = StringScanner.new('test string') | |
* s.check /\w+/ # -> "test" | |
* s.matched_size # -> 4 | |
* s.check /\d+/ # -> nil | |
* s.matched_size # -> nil | |
*/ | |
static VALUE | |
strscan_matched_size(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) return Qnil; | |
return INT2NUM(p->regs.end[0] - p->regs.beg[0]); | |
} | |
/* | |
* Equivalent to #matched_size. | |
* This method is obsolete; use #matched_size instead. | |
*/ | |
static VALUE | |
strscan_matchedsize(VALUE self) | |
{ | |
rb_warning("StringScanner#matchedsize is obsolete; use #matched_size instead"); | |
return strscan_matched_size(self); | |
} | |
/* | |
* call-seq: [](n) | |
* | |
* Return the n-th subgroup in the most recent match. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.scan(/(\w+) (\w+) (\d+) /) # -> "Fri Dec 12 " | |
* s[0] # -> "Fri Dec 12 " | |
* s[1] # -> "Fri" | |
* s[2] # -> "Dec" | |
* s[3] # -> "12" | |
* s.post_match # -> "1975 14:39" | |
* s.pre_match # -> "" | |
*/ | |
static VALUE | |
strscan_aref(VALUE self, VALUE idx) | |
{ | |
struct strscanner *p; | |
long i; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) return Qnil; | |
i = NUM2LONG(idx); | |
if (i < 0) | |
i += p->regs.num_regs; | |
if (i < 0) return Qnil; | |
if (i >= p->regs.num_regs) return Qnil; | |
if (p->regs.beg[i] == -1) return Qnil; | |
return extract_range(p, p->prev + p->regs.beg[i], | |
p->prev + p->regs.end[i]); | |
} | |
/* | |
* call-seq: size | |
* | |
* Return the amount of subgroups in the most recent match. | |
# The full match counts as a subgroup. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.scan(/(\w+) (\w+) (\d+) /) # -> "Fri Dec 12 " | |
* s.size # -> 4 | |
*/ | |
static VALUE | |
strscan_size(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) return Qnil; | |
return INT2FIX(p->regs.num_regs); | |
} | |
/* | |
* call-seq: size | |
* | |
* Returns the subgroups in the most recent match (not including the full match). | |
# If nothing was priorly matched, it returns nil. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.scan(/(\w+) (\w+) (\d+) /) # -> "Fri Dec 12 " | |
* s.captures # -> ["Fri", "Dec", "12"] | |
* s.scan(/(\w+) (\w+) (\d+) /) # -> nil | |
# s.captures # -> nil | |
*/ | |
static VALUE | |
strscan_captures(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) return Qnil; | |
int i; | |
int num_regs = p->regs.num_regs; | |
VALUE result = rb_ary_new2(num_regs); | |
for(i=1; i<num_regs; i++) { | |
rb_ary_push( | |
result, | |
extract_range(p, p->prev + p->regs.beg[i], p->prev + p->regs.end[i]) | |
); | |
} | |
return result; | |
} | |
/* | |
* call-seq: | |
* scanner.values_at( i1, i2, ... iN ) -> an_array | |
* | |
* Returns the subgroups in the most recent match at the given indices. | |
# If nothing was priorly matched, it returns nil. | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.scan(/(\w+) (\w+) (\d+) /) # -> "Fri Dec 12 " | |
* s.values_at 0, -1, 5, 2 # -> ["Fri Dec 12 ", "12", nil, "Dec"] | |
* s.scan(/(\w+) (\w+) (\d+) /) # -> nil | |
# s.captures # -> nil | |
*/ | |
static VALUE | |
strscan_values_at(int argc, VALUE *argv, VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) return Qnil; | |
long i; | |
VALUE new_ary = rb_ary_new2(argc); | |
for (i=0; i<argc; i++) { | |
rb_ary_push(new_ary, strscan_aref(self, argv[i])); | |
} | |
return new_ary; | |
} | |
/* | |
* Return the <i><b>pre</b>-match</i> (in the regular expression sense) of the last scan. | |
* | |
* s = StringScanner.new('test string') | |
* s.scan(/\w+/) # -> "test" | |
* s.scan(/\s+/) # -> " " | |
* s.pre_match # -> "test" | |
* s.post_match # -> "string" | |
*/ | |
static VALUE | |
strscan_pre_match(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) return Qnil; | |
return extract_range(p, 0, p->prev + p->regs.beg[0]); | |
} | |
/* | |
* Return the <i><b>post</b>-match</i> (in the regular expression sense) of the last scan. | |
* | |
* s = StringScanner.new('test string') | |
* s.scan(/\w+/) # -> "test" | |
* s.scan(/\s+/) # -> " " | |
* s.pre_match # -> "test" | |
* s.post_match # -> "string" | |
*/ | |
static VALUE | |
strscan_post_match(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (! MATCHED_P(p)) return Qnil; | |
return extract_range(p, p->prev + p->regs.end[0], S_LEN(p)); | |
} | |
/* | |
* Returns the "rest" of the string (i.e. everything after the scan pointer). | |
* If there is no more data (eos? = true), it returns <tt>""</tt>. | |
*/ | |
static VALUE | |
strscan_rest(VALUE self) | |
{ | |
struct strscanner *p; | |
GET_SCANNER(self, p); | |
if (EOS_P(p)) { | |
return infect(rb_str_new("", 0), p); | |
} | |
return extract_range(p, p->curr, S_LEN(p)); | |
} | |
/* | |
* <tt>s.rest_size</tt> is equivalent to <tt>s.rest.size</tt>. | |
*/ | |
static VALUE | |
strscan_rest_size(VALUE self) | |
{ | |
struct strscanner *p; | |
long i; | |
GET_SCANNER(self, p); | |
if (EOS_P(p)) { | |
return INT2FIX(0); | |
} | |
i = S_LEN(p) - p->curr; | |
return INT2FIX(i); | |
} | |
/* | |
* <tt>s.restsize</tt> is equivalent to <tt>s.rest_size</tt>. | |
* This method is obsolete; use #rest_size instead. | |
*/ | |
static VALUE | |
strscan_restsize(VALUE self) | |
{ | |
rb_warning("StringScanner#restsize is obsolete; use #rest_size instead"); | |
return strscan_rest_size(self); | |
} | |
#define INSPECT_LENGTH 5 | |
#define BUFSIZE 256 | |
/* | |
* Returns a string that represents the StringScanner object, showing: | |
* - the current position | |
* - the size of the string | |
* - the characters surrounding the scan pointer | |
* | |
* s = StringScanner.new("Fri Dec 12 1975 14:39") | |
* s.inspect # -> '#<StringScanner 0/21 @ "Fri D...">' | |
* s.scan_until /12/ # -> "Fri Dec 12" | |
* s.inspect # -> '#<StringScanner 10/21 "...ec 12" @ " 1975...">' | |
*/ | |
static VALUE | |
strscan_inspect(VALUE self) | |
{ | |
struct strscanner *p; | |
char buf[BUFSIZE]; | |
long len; | |
VALUE a, b; | |
Data_Get_Struct(self, struct strscanner, p); | |
if (NIL_P(p->str)) { | |
len = snprintf(buf, BUFSIZE, "#<%s (uninitialized)>", | |
rb_class2name(CLASS_OF(self))); | |
return infect(rb_str_new(buf, len), p); | |
} | |
if (EOS_P(p)) { | |
len = snprintf(buf, BUFSIZE, "#<%s fin>", | |
rb_class2name(CLASS_OF(self))); | |
return infect(rb_str_new(buf, len), p); | |
} | |
if (p->curr == 0) { | |
b = inspect2(p); | |
len = snprintf(buf, BUFSIZE, "#<%s %ld/%ld @ %s>", | |
rb_class2name(CLASS_OF(self)), | |
p->curr, S_LEN(p), | |
RSTRING(b)->ptr); | |
return infect(rb_str_new(buf, len), p); | |
} | |
a = inspect1(p); | |
b = inspect2(p); | |
len = snprintf(buf, BUFSIZE, "#<%s %ld/%ld %s @ %s>", | |
rb_class2name(CLASS_OF(self)), | |
p->curr, S_LEN(p), | |
RSTRING(a)->ptr, | |
RSTRING(b)->ptr); | |
return infect(rb_str_new(buf, len), p); | |
} | |
static VALUE | |
inspect1(struct strscanner *p) | |
{ | |
char buf[BUFSIZE]; | |
char *bp = buf; | |
long len; | |
if (p->curr == 0) return rb_str_new2(""); | |
if (p->curr > INSPECT_LENGTH) { | |
strcpy(bp, "..."); bp += 3; | |
len = INSPECT_LENGTH; | |
} | |
else { | |
len = p->curr; | |
} | |
memcpy(bp, CURPTR(p) - len, len); bp += len; | |
return rb_str_dump(rb_str_new(buf, bp - buf)); | |
} | |
static VALUE | |
inspect2(struct strscanner *p) | |
{ | |
char buf[BUFSIZE]; | |
char *bp = buf; | |
long len; | |
if (EOS_P(p)) return rb_str_new2(""); | |
len = S_LEN(p) - p->curr; | |
if (len > INSPECT_LENGTH) { | |
len = INSPECT_LENGTH; | |
memcpy(bp, CURPTR(p), len); bp += len; | |
strcpy(bp, "..."); bp += 3; | |
} | |
else { | |
memcpy(bp, CURPTR(p), len); bp += len; | |
} | |
return rb_str_dump(rb_str_new(buf, bp - buf)); | |
} | |
/* ======================================================================= | |
Ruby Interface | |
======================================================================= */ | |
/* | |
* Document-class: StringScanner | |
* | |
* StringScanner provides for lexical scanning operations on a String. Here is | |
* an example of its usage: | |
* | |
* s = StringScanner.new('This is an example string') | |
* s.eos? # -> false | |
* | |
* p s.scan(/\w+/) # -> "This" | |
* p s.scan(/\w+/) # -> nil | |
* p s.scan(/\s+/) # -> " " | |
* p s.scan(/\s+/) # -> nil | |
* p s.scan(/\w+/) # -> "is" | |
* s.eos? # -> false | |
* | |
* p s.scan(/\s+/) # -> " " | |
* p s.scan(/\w+/) # -> "an" | |
* p s.scan(/\s+/) # -> " " | |
* p s.scan(/\w+/) # -> "example" | |
* p s.scan(/\s+/) # -> " " | |
* p s.scan(/\w+/) # -> "string" | |
* s.eos? # -> true | |
* | |
* p s.scan(/\s+/) # -> nil | |
* p s.scan(/\w+/) # -> nil | |
* | |
* Scanning a string means remembering the position of a <i>scan pointer</i>, | |
* which is just an index. The point of scanning is to move forward a bit at | |
* a time, so matches are sought after the scan pointer; usually immediately | |
* after it. | |
* | |
* Given the string "test string", here are the pertinent scan pointer | |
* positions: | |
* | |
* t e s t s t r i n g | |
* 0 1 2 ... 1 | |
* 0 | |
* | |
* When you #scan for a pattern (a regular expression), the match must occur | |
* at the character after the scan pointer. If you use #scan_until, then the | |
* match can occur anywhere after the scan pointer. In both cases, the scan | |
* pointer moves <i>just beyond</i> the last character of the match, ready to | |
* scan again from the next character onwards. This is demonstrated by the | |
* example above. | |
* | |
* == Method Categories | |
* | |
* There are other methods besides the plain scanners. You can look ahead in | |
* the string without actually scanning. You can access the most recent match. | |
* You can modify the string being scanned, reset or terminate the scanner, | |
* find out or change the position of the scan pointer, skip ahead, and so on. | |
* | |
* === Advancing the Scan Pointer | |
* | |
* - #getch | |
* - #get_byte | |
* - #scan | |
* - #scan_until | |
* - #skip | |
* - #skip_until | |
* | |
* === Looking Ahead | |
* | |
* - #check | |
* - #check_until | |
* - #exist? | |
* - #match? | |
* - #peek | |
* | |
* === Finding Where we Are | |
* | |
* - #beginning_of_line? (#bol?) | |
* - #eos? | |
* - #rest? | |
* - #rest_size | |
* - #pos | |
* | |
* === Setting Where we Are | |
* | |
* - #reset | |
* - #terminate | |
* - #pos= | |
* | |
* === Match Data | |
* | |
* - #matched | |
* - #matched? | |
* - #matched_size | |
* - [] | |
* - #pre_match | |
* - #post_match | |
* | |
* === Miscellaneous | |
* | |
* - << | |
* - #concat | |
* - #string | |
* - #string= | |
* - #unscan | |
* | |
* There are aliases to several of the methods. | |
*/ | |
void | |
Init_strscan(void) | |
{ | |
ID id_scanerr = rb_intern("ScanError"); | |
VALUE tmp; | |
StringScanner = rb_define_class("StringScanner", rb_cObject); | |
ScanError = rb_define_class_under(StringScanner, "Error", rb_eStandardError); | |
if (!rb_const_defined(rb_cObject, id_scanerr)) { | |
rb_const_set(rb_cObject, id_scanerr, ScanError); | |
} | |
tmp = rb_str_new2(STRSCAN_VERSION); | |
rb_obj_freeze(tmp); | |
rb_const_set(StringScanner, rb_intern("Version"), tmp); | |
tmp = rb_str_new2("$Id: strscan.c 11708 2007-02-12 23:01:19Z shyouhei $"); | |
rb_obj_freeze(tmp); | |
rb_const_set(StringScanner, rb_intern("Id"), tmp); | |
rb_define_alloc_func(StringScanner, strscan_s_allocate); | |
rb_define_private_method(StringScanner, "initialize", strscan_initialize, -1); | |
rb_define_private_method(StringScanner, "initialize_copy", strscan_init_copy, 1); | |
rb_define_singleton_method(StringScanner, "must_C_version", strscan_s_mustc, 0); | |
rb_define_method(StringScanner, "reset", strscan_reset, 0); | |
rb_define_method(StringScanner, "terminate", strscan_terminate, 0); | |
rb_define_method(StringScanner, "clear", strscan_clear, 0); | |
rb_define_method(StringScanner, "string", strscan_get_string, 0); | |
rb_define_method(StringScanner, "string=", strscan_set_string, 1); | |
rb_define_method(StringScanner, "concat", strscan_concat, 1); | |
rb_define_method(StringScanner, "<<", strscan_concat, 1); | |
rb_define_method(StringScanner, "pos", strscan_get_pos, 0); | |
rb_define_method(StringScanner, "pos=", strscan_set_pos, 1); | |
rb_define_method(StringScanner, "pointer", strscan_get_pos, 0); | |
rb_define_method(StringScanner, "pointer=", strscan_set_pos, 1); | |
rb_define_method(StringScanner, "scan", strscan_scan, 1); | |
rb_define_method(StringScanner, "skip", strscan_skip, 1); | |
rb_define_method(StringScanner, "match?", strscan_match_p, 1); | |
rb_define_method(StringScanner, "check", strscan_check, 1); | |
rb_define_method(StringScanner, "scan_full", strscan_scan_full, 3); | |
rb_define_method(StringScanner, "scan_until", strscan_scan_until, 1); | |
rb_define_method(StringScanner, "skip_until", strscan_skip_until, 1); | |
rb_define_method(StringScanner, "exist?", strscan_exist_p, 1); | |
rb_define_method(StringScanner, "check_until", strscan_check_until, 1); | |
rb_define_method(StringScanner, "search_full", strscan_search_full, 3); | |
rb_define_method(StringScanner, "getch", strscan_getch, 0); | |
rb_define_method(StringScanner, "get_byte", strscan_get_byte, 0); | |
rb_define_method(StringScanner, "getbyte", strscan_getbyte, 0); | |
rb_define_method(StringScanner, "peek", strscan_peek, 1); | |
rb_define_method(StringScanner, "peep", strscan_peep, 1); | |
rb_define_method(StringScanner, "unscan", strscan_unscan, 0); | |
rb_define_method(StringScanner, "beginning_of_line?", strscan_bol_p, 0); | |
rb_alias(StringScanner, rb_intern("bol?"), rb_intern("beginning_of_line?")); | |
rb_define_method(StringScanner, "eos?", strscan_eos_p, 0); | |
rb_define_method(StringScanner, "empty?", strscan_empty_p, 0); | |
rb_define_method(StringScanner, "rest?", strscan_rest_p, 0); | |
rb_define_method(StringScanner, "matched?", strscan_matched_p, 0); | |
rb_define_method(StringScanner, "matched", strscan_matched, 0); | |
rb_define_method(StringScanner, "matched_size", strscan_matched_size, 0); | |
rb_define_method(StringScanner, "matchedsize", strscan_matchedsize, 0); | |
rb_define_method(StringScanner, "[]", strscan_aref, 1); | |
rb_define_method(StringScanner, "pre_match", strscan_pre_match, 0); | |
rb_define_method(StringScanner, "post_match", strscan_post_match, 0); | |
rb_define_method(StringScanner, "size", strscan_size, 0); | |
rb_define_method(StringScanner, "captures", strscan_captures, 0); | |
rb_define_method(StringScanner, "values_at", strscan_values_at, -1); | |
rb_define_method(StringScanner, "rest", strscan_rest, 0); | |
rb_define_method(StringScanner, "rest_size", strscan_rest_size, 0); | |
rb_define_method(StringScanner, "restsize", strscan_restsize, 0); | |
rb_define_method(StringScanner, "inspect", strscan_inspect, 0); | |
} | |
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