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			* The lexer, which include the actual lexeme producing logic, goes into the `lexer` directory. * The wrappers, one wrapper per input mode (file, string, utf-8, and readline), go into the `tokenizer` directory and include logic for creating a lexer instance and managing the buffer for different modes. --------- Co-authored-by: Pablo Galindo <pablogsal@gmail.com> Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
		
			
				
	
	
		
			76 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include "Python.h"
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| #include "errcode.h"
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| 
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| #include "state.h"
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| 
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| /* Traverse and remember all f-string buffers, in order to be able to restore
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|    them after reallocating tok->buf */
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| void
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| _PyLexer_remember_fstring_buffers(struct tok_state *tok)
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| {
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|     int index;
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|     tokenizer_mode *mode;
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| 
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|     for (index = tok->tok_mode_stack_index; index >= 0; --index) {
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|         mode = &(tok->tok_mode_stack[index]);
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|         mode->f_string_start_offset = mode->f_string_start - tok->buf;
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|         mode->f_string_multi_line_start_offset = mode->f_string_multi_line_start - tok->buf;
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|     }
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| }
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| 
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| /* Traverse and restore all f-string buffers after reallocating tok->buf */
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| void
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| _PyLexer_restore_fstring_buffers(struct tok_state *tok)
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| {
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|     int index;
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|     tokenizer_mode *mode;
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| 
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|     for (index = tok->tok_mode_stack_index; index >= 0; --index) {
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|         mode = &(tok->tok_mode_stack[index]);
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|         mode->f_string_start = tok->buf + mode->f_string_start_offset;
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|         mode->f_string_multi_line_start = tok->buf + mode->f_string_multi_line_start_offset;
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|     }
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| }
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| 
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| /* Read a line of text from TOK into S, using the stream in TOK.
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|    Return NULL on failure, else S.
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| 
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|    On entry, tok->decoding_buffer will be one of:
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|      1) NULL: need to call tok->decoding_readline to get a new line
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|      2) PyUnicodeObject *: decoding_feof has called tok->decoding_readline and
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|        stored the result in tok->decoding_buffer
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|      3) PyByteArrayObject *: previous call to tok_readline_recode did not have enough room
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|        (in the s buffer) to copy entire contents of the line read
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|        by tok->decoding_readline.  tok->decoding_buffer has the overflow.
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|        In this case, tok_readline_recode is called in a loop (with an expanded buffer)
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|        until the buffer ends with a '\n' (or until the end of the file is
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|        reached): see tok_nextc and its calls to tok_reserve_buf.
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| */
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| int
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| _PyLexer_tok_reserve_buf(struct tok_state *tok, Py_ssize_t size)
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| {
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|     Py_ssize_t cur = tok->cur - tok->buf;
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|     Py_ssize_t oldsize = tok->inp - tok->buf;
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|     Py_ssize_t newsize = oldsize + Py_MAX(size, oldsize >> 1);
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|     if (newsize > tok->end - tok->buf) {
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|         char *newbuf = tok->buf;
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|         Py_ssize_t start = tok->start == NULL ? -1 : tok->start - tok->buf;
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|         Py_ssize_t line_start = tok->start == NULL ? -1 : tok->line_start - tok->buf;
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|         Py_ssize_t multi_line_start = tok->multi_line_start - tok->buf;
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|         _PyLexer_remember_fstring_buffers(tok);
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|         newbuf = (char *)PyMem_Realloc(newbuf, newsize);
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|         if (newbuf == NULL) {
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|             tok->done = E_NOMEM;
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|             return 0;
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|         }
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|         tok->buf = newbuf;
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|         tok->cur = tok->buf + cur;
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|         tok->inp = tok->buf + oldsize;
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|         tok->end = tok->buf + newsize;
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|         tok->start = start < 0 ? NULL : tok->buf + start;
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|         tok->line_start = line_start < 0 ? NULL : tok->buf + line_start;
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|         tok->multi_line_start = multi_line_start < 0 ? NULL : tok->buf + multi_line_start;
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|         _PyLexer_restore_fstring_buffers(tok);
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|     }
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|     return 1;
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| }
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