ref: 1fe3143e4c43ce2c74e0cfdd70b1bd556bbb9e1b
dir: /sys/src/cmd/python/Parser/tokenizer.c/
/* Tokenizer implementation */ #include "Python.h" #include "pgenheaders.h" #include <ctype.h> #include <assert.h> #include "tokenizer.h" #include "errcode.h" #ifndef PGEN #include "unicodeobject.h" #include "stringobject.h" #include "fileobject.h" #include "codecs.h" #include "abstract.h" #endif /* PGEN */ extern char *PyOS_Readline(FILE *, FILE *, char *); /* Return malloc'ed string including trailing \n; empty malloc'ed string for EOF; NULL if interrupted */ /* Don't ever change this -- it would break the portability of Python code */ #define TABSIZE 8 /* Convert a possibly signed character to a nonnegative int */ /* XXX This assumes characters are 8 bits wide */ #ifdef __CHAR_UNSIGNED__ #define Py_CHARMASK(c) (c) #else #define Py_CHARMASK(c) ((c) & 0xff) #endif /* Forward */ static struct tok_state *tok_new(void); static int tok_nextc(struct tok_state *tok); static void tok_backup(struct tok_state *tok, int c); /* Token names */ char *_PyParser_TokenNames[] = { "ENDMARKER", "NAME", "NUMBER", "STRING", "NEWLINE", "INDENT", "DEDENT", "LPAR", "RPAR", "LSQB", "RSQB", "COLON", "COMMA", "SEMI", "PLUS", "MINUS", "STAR", "SLASH", "VBAR", "AMPER", "LESS", "GREATER", "EQUAL", "DOT", "PERCENT", "BACKQUOTE", "LBRACE", "RBRACE", "EQEQUAL", "NOTEQUAL", "LESSEQUAL", "GREATEREQUAL", "TILDE", "CIRCUMFLEX", "LEFTSHIFT", "RIGHTSHIFT", "DOUBLESTAR", "PLUSEQUAL", "MINEQUAL", "STAREQUAL", "SLASHEQUAL", "PERCENTEQUAL", "AMPEREQUAL", "VBAREQUAL", "CIRCUMFLEXEQUAL", "LEFTSHIFTEQUAL", "RIGHTSHIFTEQUAL", "DOUBLESTAREQUAL", "DOUBLESLASH", "DOUBLESLASHEQUAL", "AT", /* This table must match the #defines in token.h! */ "OP", "<ERRORTOKEN>", "<N_TOKENS>" }; /* Create and initialize a new tok_state structure */ static struct tok_state * tok_new(void) { struct tok_state *tok = (struct tok_state *)PyMem_MALLOC( sizeof(struct tok_state)); if (tok == NULL) return NULL; tok->buf = tok->cur = tok->end = tok->inp = tok->start = NULL; tok->done = E_OK; tok->fp = NULL; tok->tabsize = TABSIZE; tok->indent = 0; tok->indstack[0] = 0; tok->atbol = 1; tok->pendin = 0; tok->prompt = tok->nextprompt = NULL; tok->lineno = 0; tok->level = 0; tok->filename = NULL; tok->altwarning = 0; tok->alterror = 0; tok->alttabsize = 1; tok->altindstack[0] = 0; tok->decoding_state = 0; tok->decoding_erred = 0; tok->read_coding_spec = 0; tok->encoding = NULL; tok->cont_line = 0; #ifndef PGEN tok->decoding_readline = NULL; tok->decoding_buffer = NULL; #endif return tok; } #ifdef PGEN static char * decoding_fgets(char *s, int size, struct tok_state *tok) { return fgets(s, size, tok->fp); } static int decoding_feof(struct tok_state *tok) { return feof(tok->fp); } static const char * decode_str(const char *str, struct tok_state *tok) { return str; } #else /* PGEN */ static char * error_ret(struct tok_state *tok) /* XXX */ { tok->decoding_erred = 1; if (tok->fp != NULL && tok->buf != NULL) /* see PyTokenizer_Free */ PyMem_FREE(tok->buf); tok->buf = NULL; return NULL; /* as if it were EOF */ } static char * new_string(const char *s, Py_ssize_t len) { char* result = (char *)PyMem_MALLOC(len + 1); if (result != NULL) { memcpy(result, s, len); result[len] = '\0'; } return result; } static char * get_normal_name(char *s) /* for utf-8 and latin-1 */ { char buf[13]; int i; for (i = 0; i < 12; i++) { int c = s[i]; if (c == '\0') break; else if (c == '_') buf[i] = '-'; else buf[i] = tolower(c); } buf[i] = '\0'; if (strcmp(buf, "utf-8") == 0 || strncmp(buf, "utf-8-", 6) == 0) return "utf-8"; else if (strcmp(buf, "latin-1") == 0 || strcmp(buf, "iso-8859-1") == 0 || strcmp(buf, "iso-latin-1") == 0 || strncmp(buf, "latin-1-", 8) == 0 || strncmp(buf, "iso-8859-1-", 11) == 0 || strncmp(buf, "iso-latin-1-", 12) == 0) return "iso-8859-1"; else return s; } /* Return the coding spec in S, or NULL if none is found. */ static char * get_coding_spec(const char *s, Py_ssize_t size) { Py_ssize_t i; /* Coding spec must be in a comment, and that comment must be * the only statement on the source code line. */ for (i = 0; i < size - 6; i++) { if (s[i] == '#') break; if (s[i] != ' ' && s[i] != '\t' && s[i] != '\014') return NULL; } for (; i < size - 6; i++) { /* XXX inefficient search */ const char* t = s + i; if (strncmp(t, "coding", 6) == 0) { const char* begin = NULL; t += 6; if (t[0] != ':' && t[0] != '=') continue; do { t++; } while (t[0] == '\x20' || t[0] == '\t'); begin = t; while (isalnum(Py_CHARMASK(t[0])) || t[0] == '-' || t[0] == '_' || t[0] == '.') t++; if (begin < t) { char* r = new_string(begin, t - begin); char* q = get_normal_name(r); if (r != q) { PyMem_FREE(r); r = new_string(q, strlen(q)); } return r; } } } return NULL; } /* Check whether the line contains a coding spec. If it does, invoke the set_readline function for the new encoding. This function receives the tok_state and the new encoding. Return 1 on success, 0 on failure. */ static int check_coding_spec(const char* line, Py_ssize_t size, struct tok_state *tok, int set_readline(struct tok_state *, const char *)) { char * cs; int r = 1; if (tok->cont_line) /* It's a continuation line, so it can't be a coding spec. */ return 1; cs = get_coding_spec(line, size); if (cs != NULL) { tok->read_coding_spec = 1; if (tok->encoding == NULL) { assert(tok->decoding_state == 1); /* raw */ if (strcmp(cs, "utf-8") == 0 || strcmp(cs, "iso-8859-1") == 0) { tok->encoding = cs; } else { #ifdef Py_USING_UNICODE r = set_readline(tok, cs); if (r) { tok->encoding = cs; tok->decoding_state = -1; } else PyMem_FREE(cs); #else /* Without Unicode support, we cannot process the coding spec. Since there won't be any Unicode literals, that won't matter. */ PyMem_FREE(cs); #endif } } else { /* then, compare cs with BOM */ r = (strcmp(tok->encoding, cs) == 0); PyMem_FREE(cs); } } if (!r) { cs = tok->encoding; if (!cs) cs = "with BOM"; PyErr_Format(PyExc_SyntaxError, "encoding problem: %s", cs); } return r; } /* See whether the file starts with a BOM. If it does, invoke the set_readline function with the new encoding. Return 1 on success, 0 on failure. */ static int check_bom(int get_char(struct tok_state *), void unget_char(int, struct tok_state *), int set_readline(struct tok_state *, const char *), struct tok_state *tok) { int ch = get_char(tok); tok->decoding_state = 1; if (ch == EOF) { return 1; } else if (ch == 0xEF) { ch = get_char(tok); if (ch != 0xBB) goto NON_BOM; ch = get_char(tok); if (ch != 0xBF) goto NON_BOM; #if 0 /* Disable support for UTF-16 BOMs until a decision is made whether this needs to be supported. */ } else if (ch == 0xFE) { ch = get_char(tok); if (ch != 0xFF) goto NON_BOM; if (!set_readline(tok, "utf-16-be")) return 0; tok->decoding_state = -1; } else if (ch == 0xFF) { ch = get_char(tok); if (ch != 0xFE) goto NON_BOM; if (!set_readline(tok, "utf-16-le")) return 0; tok->decoding_state = -1; #endif } else { unget_char(ch, tok); return 1; } if (tok->encoding != NULL) PyMem_FREE(tok->encoding); tok->encoding = new_string("utf-8", 5); /* resulting is in utf-8 */ return 1; NON_BOM: /* any token beginning with '\xEF', '\xFE', '\xFF' is a bad token */ unget_char(0xFF, tok); /* XXX this will cause a syntax error */ return 1; } /* Read a line of text from TOK into S, using the stream in TOK. Return NULL on failure, else S. On entry, tok->decoding_buffer will be one of: 1) NULL: need to call tok->decoding_readline to get a new line 2) PyUnicodeObject *: decoding_feof has called tok->decoding_readline and stored the result in tok->decoding_buffer 3) PyStringObject *: previous call to fp_readl did not have enough room (in the s buffer) to copy entire contents of the line read by tok->decoding_readline. tok->decoding_buffer has the overflow. In this case, fp_readl is called in a loop (with an expanded buffer) until the buffer ends with a '\n' (or until the end of the file is reached): see tok_nextc and its calls to decoding_fgets. */ static char * fp_readl(char *s, int size, struct tok_state *tok) { #ifndef Py_USING_UNICODE /* In a non-Unicode built, this should never be called. */ Py_FatalError("fp_readl should not be called in this build."); return NULL; /* Keep compiler happy (not reachable) */ #else PyObject* utf8 = NULL; PyObject* buf = tok->decoding_buffer; char *str; Py_ssize_t utf8len; /* Ask for one less byte so we can terminate it */ assert(size > 0); size--; if (buf == NULL) { buf = PyObject_CallObject(tok->decoding_readline, NULL); if (buf == NULL) return error_ret(tok); } else { tok->decoding_buffer = NULL; if (PyString_CheckExact(buf)) utf8 = buf; } if (utf8 == NULL) { utf8 = PyUnicode_AsUTF8String(buf); Py_DECREF(buf); if (utf8 == NULL) return error_ret(tok); } str = PyString_AsString(utf8); utf8len = PyString_GET_SIZE(utf8); if (utf8len > size) { tok->decoding_buffer = PyString_FromStringAndSize(str+size, utf8len-size); if (tok->decoding_buffer == NULL) { Py_DECREF(utf8); return error_ret(tok); } utf8len = size; } memcpy(s, str, utf8len); s[utf8len] = '\0'; Py_DECREF(utf8); if (utf8len == 0) return NULL; /* EOF */ return s; #endif } /* Set the readline function for TOK to a StreamReader's readline function. The StreamReader is named ENC. This function is called from check_bom and check_coding_spec. ENC is usually identical to the future value of tok->encoding, except for the (currently unsupported) case of UTF-16. Return 1 on success, 0 on failure. */ static int fp_setreadl(struct tok_state *tok, const char* enc) { PyObject *reader, *stream, *readline; /* XXX: constify filename argument. */ stream = PyFile_FromFile(tok->fp, (char*)tok->filename, "rb", NULL); if (stream == NULL) return 0; reader = PyCodec_StreamReader(enc, stream, NULL); Py_DECREF(stream); if (reader == NULL) return 0; readline = PyObject_GetAttrString(reader, "readline"); Py_DECREF(reader); if (readline == NULL) return 0; tok->decoding_readline = readline; return 1; } /* Fetch the next byte from TOK. */ static int fp_getc(struct tok_state *tok) { return getc(tok->fp); } /* Unfetch the last byte back into TOK. */ static void fp_ungetc(int c, struct tok_state *tok) { ungetc(c, tok->fp); } /* Read a line of input from TOK. Determine encoding if necessary. */ static char * decoding_fgets(char *s, int size, struct tok_state *tok) { char *line = NULL; int badchar = 0; for (;;) { if (tok->decoding_state < 0) { /* We already have a codec associated with this input. */ line = fp_readl(s, size, tok); break; } else if (tok->decoding_state > 0) { /* We want a 'raw' read. */ line = Py_UniversalNewlineFgets(s, size, tok->fp, NULL); break; } else { /* We have not yet determined the encoding. If an encoding is found, use the file-pointer reader functions from now on. */ if (!check_bom(fp_getc, fp_ungetc, fp_setreadl, tok)) return error_ret(tok); assert(tok->decoding_state != 0); } } if (line != NULL && tok->lineno < 2 && !tok->read_coding_spec) { if (!check_coding_spec(line, strlen(line), tok, fp_setreadl)) { return error_ret(tok); } } #ifndef PGEN /* The default encoding is ASCII, so make sure we don't have any non-ASCII bytes in it. */ if (line && !tok->encoding) { unsigned char *c; for (c = (unsigned char *)line; *c; c++) if (*c > 127) { badchar = *c; break; } } if (badchar) { char buf[500]; /* Need to add 1 to the line number, since this line has not been counted, yet. */ sprintf(buf, "Non-ASCII character '\\x%.2x' " "in file %.200s on line %i, " "but no encoding declared; " "see http://www.python.org/peps/pep-0263.html for details", badchar, tok->filename, tok->lineno + 1); PyErr_SetString(PyExc_SyntaxError, buf); return error_ret(tok); } #endif return line; } static int decoding_feof(struct tok_state *tok) { if (tok->decoding_state >= 0) { return feof(tok->fp); } else { PyObject* buf = tok->decoding_buffer; if (buf == NULL) { buf = PyObject_CallObject(tok->decoding_readline, NULL); if (buf == NULL) { error_ret(tok); return 1; } else { tok->decoding_buffer = buf; } } return PyObject_Length(buf) == 0; } } /* Fetch a byte from TOK, using the string buffer. */ static int buf_getc(struct tok_state *tok) { return Py_CHARMASK(*tok->str++); } /* Unfetch a byte from TOK, using the string buffer. */ static void buf_ungetc(int c, struct tok_state *tok) { tok->str--; assert(Py_CHARMASK(*tok->str) == c); /* tok->cur may point to read-only segment */ } /* Set the readline function for TOK to ENC. For the string-based tokenizer, this means to just record the encoding. */ static int buf_setreadl(struct tok_state *tok, const char* enc) { tok->enc = enc; return 1; } /* Return a UTF-8 encoding Python string object from the C byte string STR, which is encoded with ENC. */ #ifdef Py_USING_UNICODE static PyObject * translate_into_utf8(const char* str, const char* enc) { PyObject *utf8; PyObject* buf = PyUnicode_Decode(str, strlen(str), enc, NULL); if (buf == NULL) return NULL; utf8 = PyUnicode_AsUTF8String(buf); Py_DECREF(buf); return utf8; } #endif /* Decode a byte string STR for use as the buffer of TOK. Look for encoding declarations inside STR, and record them inside TOK. */ static const char * decode_str(const char *str, struct tok_state *tok) { PyObject* utf8 = NULL; const char *s; int lineno = 0; tok->enc = NULL; tok->str = str; if (!check_bom(buf_getc, buf_ungetc, buf_setreadl, tok)) return error_ret(tok); str = tok->str; /* string after BOM if any */ assert(str); #ifdef Py_USING_UNICODE if (tok->enc != NULL) { utf8 = translate_into_utf8(str, tok->enc); if (utf8 == NULL) return error_ret(tok); str = PyString_AsString(utf8); } #endif for (s = str;; s++) { if (*s == '\0') break; else if (*s == '\n') { lineno++; if (lineno == 2) break; } } tok->enc = NULL; if (!check_coding_spec(str, s - str, tok, buf_setreadl)) return error_ret(tok); #ifdef Py_USING_UNICODE if (tok->enc != NULL) { assert(utf8 == NULL); utf8 = translate_into_utf8(str, tok->enc); if (utf8 == NULL) { PyErr_Format(PyExc_SyntaxError, "unknown encoding: %s", tok->enc); return error_ret(tok); } str = PyString_AsString(utf8); } #endif assert(tok->decoding_buffer == NULL); tok->decoding_buffer = utf8; /* CAUTION */ return str; } #endif /* PGEN */ /* Set up tokenizer for string */ struct tok_state * PyTokenizer_FromString(const char *str) { struct tok_state *tok = tok_new(); if (tok == NULL) return NULL; str = (char *)decode_str(str, tok); if (str == NULL) { PyTokenizer_Free(tok); return NULL; } /* XXX: constify members. */ tok->buf = tok->cur = tok->end = tok->inp = (char*)str; return tok; } /* Set up tokenizer for file */ struct tok_state * PyTokenizer_FromFile(FILE *fp, char *ps1, char *ps2) { struct tok_state *tok = tok_new(); if (tok == NULL) return NULL; if ((tok->buf = (char *)PyMem_MALLOC(BUFSIZ)) == NULL) { PyTokenizer_Free(tok); return NULL; } tok->cur = tok->inp = tok->buf; tok->end = tok->buf + BUFSIZ; tok->fp = fp; tok->prompt = ps1; tok->nextprompt = ps2; return tok; } /* Free a tok_state structure */ void PyTokenizer_Free(struct tok_state *tok) { if (tok->encoding != NULL) PyMem_FREE(tok->encoding); #ifndef PGEN Py_XDECREF(tok->decoding_readline); Py_XDECREF(tok->decoding_buffer); #endif if (tok->fp != NULL && tok->buf != NULL) PyMem_FREE(tok->buf); PyMem_FREE(tok); } #if !defined(PGEN) && defined(Py_USING_UNICODE) static int tok_stdin_decode(struct tok_state *tok, char **inp) { PyObject *enc, *sysstdin, *decoded, *utf8; const char *encoding; char *converted; if (PySys_GetFile((char *)"stdin", NULL) != stdin) return 0; sysstdin = PySys_GetObject("stdin"); if (sysstdin == NULL || !PyFile_Check(sysstdin)) return 0; enc = ((PyFileObject *)sysstdin)->f_encoding; if (enc == NULL || !PyString_Check(enc)) return 0; Py_INCREF(enc); encoding = PyString_AsString(enc); decoded = PyUnicode_Decode(*inp, strlen(*inp), encoding, NULL); if (decoded == NULL) goto error_clear; utf8 = PyUnicode_AsEncodedString(decoded, "utf-8", NULL); Py_DECREF(decoded); if (utf8 == NULL) goto error_clear; assert(PyString_Check(utf8)); converted = new_string(PyString_AS_STRING(utf8), PyString_GET_SIZE(utf8)); Py_DECREF(utf8); if (converted == NULL) goto error_nomem; PyMem_FREE(*inp); *inp = converted; if (tok->encoding != NULL) PyMem_FREE(tok->encoding); tok->encoding = new_string(encoding, strlen(encoding)); if (tok->encoding == NULL) goto error_nomem; Py_DECREF(enc); return 0; error_nomem: Py_DECREF(enc); tok->done = E_NOMEM; return -1; error_clear: /* Fallback to iso-8859-1: for backward compatibility */ Py_DECREF(enc); PyErr_Clear(); return 0; } #endif /* Get next char, updating state; error code goes into tok->done */ static int tok_nextc(register struct tok_state *tok) { for (;;) { if (tok->cur != tok->inp) { return Py_CHARMASK(*tok->cur++); /* Fast path */ } if (tok->done != E_OK) return EOF; if (tok->fp == NULL) { char *end = strchr(tok->inp, '\n'); if (end != NULL) end++; else { end = strchr(tok->inp, '\0'); if (end == tok->inp) { tok->done = E_EOF; return EOF; } } if (tok->start == NULL) tok->buf = tok->cur; tok->line_start = tok->cur; tok->lineno++; tok->inp = end; return Py_CHARMASK(*tok->cur++); } if (tok->prompt != NULL) { char *newtok = PyOS_Readline(stdin, stdout, tok->prompt); if (tok->nextprompt != NULL) tok->prompt = tok->nextprompt; if (newtok == NULL) tok->done = E_INTR; else if (*newtok == '\0') { PyMem_FREE(newtok); tok->done = E_EOF; } #if !defined(PGEN) && defined(Py_USING_UNICODE) else if (tok_stdin_decode(tok, &newtok) != 0) PyMem_FREE(newtok); #endif else if (tok->start != NULL) { size_t start = tok->start - tok->buf; size_t oldlen = tok->cur - tok->buf; size_t newlen = oldlen + strlen(newtok); char *buf = tok->buf; buf = (char *)PyMem_REALLOC(buf, newlen+1); tok->lineno++; if (buf == NULL) { PyMem_FREE(tok->buf); tok->buf = NULL; PyMem_FREE(newtok); tok->done = E_NOMEM; return EOF; } tok->buf = buf; tok->cur = tok->buf + oldlen; tok->line_start = tok->cur; strcpy(tok->buf + oldlen, newtok); PyMem_FREE(newtok); tok->inp = tok->buf + newlen; tok->end = tok->inp + 1; tok->start = tok->buf + start; } else { tok->lineno++; if (tok->buf != NULL) PyMem_FREE(tok->buf); tok->buf = newtok; tok->line_start = tok->buf; tok->cur = tok->buf; tok->line_start = tok->buf; tok->inp = strchr(tok->buf, '\0'); tok->end = tok->inp + 1; } } else { int done = 0; Py_ssize_t cur = 0; char *pt; if (tok->start == NULL) { if (tok->buf == NULL) { tok->buf = (char *) PyMem_MALLOC(BUFSIZ); if (tok->buf == NULL) { tok->done = E_NOMEM; return EOF; } tok->end = tok->buf + BUFSIZ; } if (decoding_fgets(tok->buf, (int)(tok->end - tok->buf), tok) == NULL) { tok->done = E_EOF; done = 1; } else { tok->done = E_OK; tok->inp = strchr(tok->buf, '\0'); done = tok->inp[-1] == '\n'; } } else { cur = tok->cur - tok->buf; if (decoding_feof(tok)) { tok->done = E_EOF; done = 1; } else tok->done = E_OK; } tok->lineno++; /* Read until '\n' or EOF */ while (!done) { Py_ssize_t curstart = tok->start == NULL ? -1 : tok->start - tok->buf; Py_ssize_t curvalid = tok->inp - tok->buf; Py_ssize_t newsize = curvalid + BUFSIZ; char *newbuf = tok->buf; newbuf = (char *)PyMem_REALLOC(newbuf, newsize); if (newbuf == NULL) { tok->done = E_NOMEM; tok->cur = tok->inp; return EOF; } tok->buf = newbuf; tok->inp = tok->buf + curvalid; tok->end = tok->buf + newsize; tok->start = curstart < 0 ? NULL : tok->buf + curstart; if (decoding_fgets(tok->inp, (int)(tok->end - tok->inp), tok) == NULL) { /* Break out early on decoding errors, as tok->buf will be NULL */ if (tok->decoding_erred) return EOF; /* Last line does not end in \n, fake one */ strcpy(tok->inp, "\n"); } tok->inp = strchr(tok->inp, '\0'); done = tok->inp[-1] == '\n'; } if (tok->buf != NULL) { tok->cur = tok->buf + cur; tok->line_start = tok->cur; /* replace "\r\n" with "\n" */ /* For Mac leave the \r, giving syntax error */ pt = tok->inp - 2; if (pt >= tok->buf && *pt == '\r') { *pt++ = '\n'; *pt = '\0'; tok->inp = pt; } } } if (tok->done != E_OK) { if (tok->prompt != NULL) PySys_WriteStderr("\n"); tok->cur = tok->inp; return EOF; } } /*NOTREACHED*/ } /* Back-up one character */ static void tok_backup(register struct tok_state *tok, register int c) { if (c != EOF) { if (--tok->cur < tok->buf) Py_FatalError("tok_backup: begin of buffer"); if (*tok->cur != c) *tok->cur = c; } } /* Return the token corresponding to a single character */ int PyToken_OneChar(int c) { switch (c) { case '(': return LPAR; case ')': return RPAR; case '[': return LSQB; case ']': return RSQB; case ':': return COLON; case ',': return COMMA; case ';': return SEMI; case '+': return PLUS; case '-': return MINUS; case '*': return STAR; case '/': return SLASH; case '|': return VBAR; case '&': return AMPER; case '<': return LESS; case '>': return GREATER; case '=': return EQUAL; case '.': return DOT; case '%': return PERCENT; case '`': return BACKQUOTE; case '{': return LBRACE; case '}': return RBRACE; case '^': return CIRCUMFLEX; case '~': return TILDE; case '@': return AT; default: return OP; } } int PyToken_TwoChars(int c1, int c2) { switch (c1) { case '=': switch (c2) { case '=': return EQEQUAL; } break; case '!': switch (c2) { case '=': return NOTEQUAL; } break; case '<': switch (c2) { case '>': return NOTEQUAL; case '=': return LESSEQUAL; case '<': return LEFTSHIFT; } break; case '>': switch (c2) { case '=': return GREATEREQUAL; case '>': return RIGHTSHIFT; } break; case '+': switch (c2) { case '=': return PLUSEQUAL; } break; case '-': switch (c2) { case '=': return MINEQUAL; } break; case '*': switch (c2) { case '*': return DOUBLESTAR; case '=': return STAREQUAL; } break; case '/': switch (c2) { case '/': return DOUBLESLASH; case '=': return SLASHEQUAL; } break; case '|': switch (c2) { case '=': return VBAREQUAL; } break; case '%': switch (c2) { case '=': return PERCENTEQUAL; } break; case '&': switch (c2) { case '=': return AMPEREQUAL; } break; case '^': switch (c2) { case '=': return CIRCUMFLEXEQUAL; } break; } return OP; } int PyToken_ThreeChars(int c1, int c2, int c3) { switch (c1) { case '<': switch (c2) { case '<': switch (c3) { case '=': return LEFTSHIFTEQUAL; } break; } break; case '>': switch (c2) { case '>': switch (c3) { case '=': return RIGHTSHIFTEQUAL; } break; } break; case '*': switch (c2) { case '*': switch (c3) { case '=': return DOUBLESTAREQUAL; } break; } break; case '/': switch (c2) { case '/': switch (c3) { case '=': return DOUBLESLASHEQUAL; } break; } break; } return OP; } static int indenterror(struct tok_state *tok) { if (tok->alterror) { tok->done = E_TABSPACE; tok->cur = tok->inp; return 1; } if (tok->altwarning) { PySys_WriteStderr("%s: inconsistent use of tabs and spaces " "in indentation\n", tok->filename); tok->altwarning = 0; } return 0; } /* Get next token, after space stripping etc. */ static int tok_get(register struct tok_state *tok, char **p_start, char **p_end) { register int c; int blankline; *p_start = *p_end = NULL; nextline: tok->start = NULL; blankline = 0; /* Get indentation level */ if (tok->atbol) { register int col = 0; register int altcol = 0; tok->atbol = 0; for (;;) { c = tok_nextc(tok); if (c == ' ') col++, altcol++; else if (c == '\t') { col = (col/tok->tabsize + 1) * tok->tabsize; altcol = (altcol/tok->alttabsize + 1) * tok->alttabsize; } else if (c == '\014') /* Control-L (formfeed) */ col = altcol = 0; /* For Emacs users */ else break; } tok_backup(tok, c); if (c == '#' || c == '\n') { /* Lines with only whitespace and/or comments shouldn't affect the indentation and are not passed to the parser as NEWLINE tokens, except *totally* empty lines in interactive mode, which signal the end of a command group. */ if (col == 0 && c == '\n' && tok->prompt != NULL) blankline = 0; /* Let it through */ else blankline = 1; /* Ignore completely */ /* We can't jump back right here since we still may need to skip to the end of a comment */ } if (!blankline && tok->level == 0) { if (col == tok->indstack[tok->indent]) { /* No change */ if (altcol != tok->altindstack[tok->indent]) { if (indenterror(tok)) return ERRORTOKEN; } } else if (col > tok->indstack[tok->indent]) { /* Indent -- always one */ if (tok->indent+1 >= MAXINDENT) { tok->done = E_TOODEEP; tok->cur = tok->inp; return ERRORTOKEN; } if (altcol <= tok->altindstack[tok->indent]) { if (indenterror(tok)) return ERRORTOKEN; } tok->pendin++; tok->indstack[++tok->indent] = col; tok->altindstack[tok->indent] = altcol; } else /* col < tok->indstack[tok->indent] */ { /* Dedent -- any number, must be consistent */ while (tok->indent > 0 && col < tok->indstack[tok->indent]) { tok->pendin--; tok->indent--; } if (col != tok->indstack[tok->indent]) { tok->done = E_DEDENT; tok->cur = tok->inp; return ERRORTOKEN; } if (altcol != tok->altindstack[tok->indent]) { if (indenterror(tok)) return ERRORTOKEN; } } } } tok->start = tok->cur; /* Return pending indents/dedents */ if (tok->pendin != 0) { if (tok->pendin < 0) { tok->pendin++; return DEDENT; } else { tok->pendin--; return INDENT; } } again: tok->start = NULL; /* Skip spaces */ do { c = tok_nextc(tok); } while (c == ' ' || c == '\t' || c == '\014'); /* Set start of current token */ tok->start = tok->cur - 1; /* Skip comment, while looking for tab-setting magic */ if (c == '#') { static char *tabforms[] = { "tab-width:", /* Emacs */ ":tabstop=", /* vim, full form */ ":ts=", /* vim, abbreviated form */ "set tabsize=", /* will vi never die? */ /* more templates can be added here to support other editors */ }; char cbuf[80]; char *tp, **cp; tp = cbuf; do { *tp++ = c = tok_nextc(tok); } while (c != EOF && c != '\n' && (size_t)(tp - cbuf + 1) < sizeof(cbuf)); *tp = '\0'; for (cp = tabforms; cp < tabforms + sizeof(tabforms)/sizeof(tabforms[0]); cp++) { if ((tp = strstr(cbuf, *cp))) { int newsize = atoi(tp + strlen(*cp)); if (newsize >= 1 && newsize <= 40) { tok->tabsize = newsize; if (Py_VerboseFlag) PySys_WriteStderr( "Tab size set to %d\n", newsize); } } } while (c != EOF && c != '\n') c = tok_nextc(tok); } /* Check for EOF and errors now */ if (c == EOF) { return tok->done == E_EOF ? ENDMARKER : ERRORTOKEN; } /* Identifier (most frequent token!) */ if (isalpha(c) || c == '_') { /* Process r"", u"" and ur"" */ switch (c) { case 'r': case 'R': c = tok_nextc(tok); if (c == '"' || c == '\'') goto letter_quote; break; case 'u': case 'U': c = tok_nextc(tok); if (c == 'r' || c == 'R') c = tok_nextc(tok); if (c == '"' || c == '\'') goto letter_quote; break; } while (isalnum(c) || c == '_') { c = tok_nextc(tok); } tok_backup(tok, c); *p_start = tok->start; *p_end = tok->cur; return NAME; } /* Newline */ if (c == '\n') { tok->atbol = 1; if (blankline || tok->level > 0) goto nextline; *p_start = tok->start; *p_end = tok->cur - 1; /* Leave '\n' out of the string */ tok->cont_line = 0; return NEWLINE; } /* Period or number starting with period? */ if (c == '.') { c = tok_nextc(tok); if (isdigit(c)) { goto fraction; } else { tok_backup(tok, c); *p_start = tok->start; *p_end = tok->cur; return DOT; } } /* Number */ if (isdigit(c)) { if (c == '0') { /* Hex or octal -- maybe. */ c = tok_nextc(tok); if (c == '.') goto fraction; #ifndef WITHOUT_COMPLEX if (c == 'j' || c == 'J') goto imaginary; #endif if (c == 'x' || c == 'X') { /* Hex */ do { c = tok_nextc(tok); } while (isxdigit(c)); } else { int found_decimal = 0; /* Octal; c is first char of it */ /* There's no 'isoctdigit' macro, sigh */ while ('0' <= c && c < '8') { c = tok_nextc(tok); } if (isdigit(c)) { found_decimal = 1; do { c = tok_nextc(tok); } while (isdigit(c)); } if (c == '.') goto fraction; else if (c == 'e' || c == 'E') goto exponent; #ifndef WITHOUT_COMPLEX else if (c == 'j' || c == 'J') goto imaginary; #endif else if (found_decimal) { tok->done = E_TOKEN; tok_backup(tok, c); return ERRORTOKEN; } } if (c == 'l' || c == 'L') c = tok_nextc(tok); } else { /* Decimal */ do { c = tok_nextc(tok); } while (isdigit(c)); if (c == 'l' || c == 'L') c = tok_nextc(tok); else { /* Accept floating point numbers. */ if (c == '.') { fraction: /* Fraction */ do { c = tok_nextc(tok); } while (isdigit(c)); } if (c == 'e' || c == 'E') { exponent: /* Exponent part */ c = tok_nextc(tok); if (c == '+' || c == '-') c = tok_nextc(tok); if (!isdigit(c)) { tok->done = E_TOKEN; tok_backup(tok, c); return ERRORTOKEN; } do { c = tok_nextc(tok); } while (isdigit(c)); } #ifndef WITHOUT_COMPLEX if (c == 'j' || c == 'J') /* Imaginary part */ imaginary: c = tok_nextc(tok); #endif } } tok_backup(tok, c); *p_start = tok->start; *p_end = tok->cur; return NUMBER; } letter_quote: /* String */ if (c == '\'' || c == '"') { Py_ssize_t quote2 = tok->cur - tok->start + 1; int quote = c; int triple = 0; int tripcount = 0; for (;;) { c = tok_nextc(tok); if (c == '\n') { if (!triple) { tok->done = E_EOLS; tok_backup(tok, c); return ERRORTOKEN; } tripcount = 0; tok->cont_line = 1; /* multiline string. */ } else if (c == EOF) { if (triple) tok->done = E_EOFS; else tok->done = E_EOLS; tok->cur = tok->inp; return ERRORTOKEN; } else if (c == quote) { tripcount++; if (tok->cur - tok->start == quote2) { c = tok_nextc(tok); if (c == quote) { triple = 1; tripcount = 0; continue; } tok_backup(tok, c); } if (!triple || tripcount == 3) break; } else if (c == '\\') { tripcount = 0; c = tok_nextc(tok); if (c == EOF) { tok->done = E_EOLS; tok->cur = tok->inp; return ERRORTOKEN; } } else tripcount = 0; } *p_start = tok->start; *p_end = tok->cur; return STRING; } /* Line continuation */ if (c == '\\') { c = tok_nextc(tok); if (c != '\n') { tok->done = E_LINECONT; tok->cur = tok->inp; return ERRORTOKEN; } tok->cont_line = 1; goto again; /* Read next line */ } /* Check for two-character token */ { int c2 = tok_nextc(tok); int token = PyToken_TwoChars(c, c2); if (token != OP) { int c3 = tok_nextc(tok); int token3 = PyToken_ThreeChars(c, c2, c3); if (token3 != OP) { token = token3; } else { tok_backup(tok, c3); } *p_start = tok->start; *p_end = tok->cur; return token; } tok_backup(tok, c2); } /* Keep track of parentheses nesting level */ switch (c) { case '(': case '[': case '{': tok->level++; break; case ')': case ']': case '}': tok->level--; break; } /* Punctuation character */ *p_start = tok->start; *p_end = tok->cur; return PyToken_OneChar(c); } int PyTokenizer_Get(struct tok_state *tok, char **p_start, char **p_end) { int result = tok_get(tok, p_start, p_end); if (tok->decoding_erred) { result = ERRORTOKEN; tok->done = E_DECODE; } return result; } #ifdef Py_DEBUG void tok_dump(int type, char *start, char *end) { printf("%s", _PyParser_TokenNames[type]); if (type == NAME || type == NUMBER || type == STRING || type == OP) printf("(%.*s)", (int)(end - start), start); } #endif