ref: 5513dae7d9eee46f7e1843c8eeeaf9066d0ec632
dir: /sys/src/cmd/python/Parser/parsetok.c/
/* Parser-tokenizer link implementation */ #include "pgenheaders.h" #include "tokenizer.h" #include "node.h" #include "grammar.h" #include "parser.h" #include "parsetok.h" #include "errcode.h" #include "graminit.h" int Py_TabcheckFlag; /* Forward */ static node *parsetok(struct tok_state *, grammar *, int, perrdetail *, int); static void initerr(perrdetail *err_ret, const char* filename); /* Parse input coming from a string. Return error code, print some errors. */ node * PyParser_ParseString(const char *s, grammar *g, int start, perrdetail *err_ret) { return PyParser_ParseStringFlagsFilename(s, NULL, g, start, err_ret, 0); } node * PyParser_ParseStringFlags(const char *s, grammar *g, int start, perrdetail *err_ret, int flags) { return PyParser_ParseStringFlagsFilename(s, NULL, g, start, err_ret, flags); } node * PyParser_ParseStringFlagsFilename(const char *s, const char *filename, grammar *g, int start, perrdetail *err_ret, int flags) { struct tok_state *tok; initerr(err_ret, filename); if ((tok = PyTokenizer_FromString(s)) == NULL) { err_ret->error = PyErr_Occurred() ? E_DECODE : E_NOMEM; return NULL; } tok->filename = filename ? filename : "<string>"; if (Py_TabcheckFlag || Py_VerboseFlag) { tok->altwarning = (tok->filename != NULL); if (Py_TabcheckFlag >= 2) tok->alterror++; } return parsetok(tok, g, start, err_ret, flags); } /* Parse input coming from a file. Return error code, print some errors. */ node * PyParser_ParseFile(FILE *fp, const char *filename, grammar *g, int start, char *ps1, char *ps2, perrdetail *err_ret) { return PyParser_ParseFileFlags(fp, filename, g, start, ps1, ps2, err_ret, 0); } node * PyParser_ParseFileFlags(FILE *fp, const char *filename, grammar *g, int start, char *ps1, char *ps2, perrdetail *err_ret, int flags) { struct tok_state *tok; initerr(err_ret, filename); if ((tok = PyTokenizer_FromFile(fp, ps1, ps2)) == NULL) { err_ret->error = E_NOMEM; return NULL; } tok->filename = filename; if (Py_TabcheckFlag || Py_VerboseFlag) { tok->altwarning = (filename != NULL); if (Py_TabcheckFlag >= 2) tok->alterror++; } return parsetok(tok, g, start, err_ret, flags); } /* Parse input coming from the given tokenizer structure. Return error code. */ static char with_msg[] = "%s:%d: Warning: 'with' will become a reserved keyword in Python 2.6\n"; static char as_msg[] = "%s:%d: Warning: 'as' will become a reserved keyword in Python 2.6\n"; static void warn(const char *msg, const char *filename, int lineno) { if (filename == NULL) filename = "<string>"; PySys_WriteStderr(msg, filename, lineno); } static node * parsetok(struct tok_state *tok, grammar *g, int start, perrdetail *err_ret, int flags) { parser_state *ps; node *n; int started = 0, handling_import = 0, handling_with = 0; if ((ps = PyParser_New(g, start)) == NULL) { fprintf(stderr, "no mem for new parser\n"); err_ret->error = E_NOMEM; PyTokenizer_Free(tok); return NULL; } #ifdef PY_PARSER_REQUIRES_FUTURE_KEYWORD if (flags & PyPARSE_WITH_IS_KEYWORD) ps->p_flags |= CO_FUTURE_WITH_STATEMENT; #endif for (;;) { char *a, *b; int type; size_t len; char *str; int col_offset; type = PyTokenizer_Get(tok, &a, &b); if (type == ERRORTOKEN) { err_ret->error = tok->done; break; } if (type == ENDMARKER && started) { type = NEWLINE; /* Add an extra newline */ handling_with = handling_import = 0; started = 0; /* Add the right number of dedent tokens, except if a certain flag is given -- codeop.py uses this. */ if (tok->indent && !(flags & PyPARSE_DONT_IMPLY_DEDENT)) { tok->pendin = -tok->indent; tok->indent = 0; } } else started = 1; len = b - a; /* XXX this may compute NULL - NULL */ str = (char *) PyObject_MALLOC(len + 1); if (str == NULL) { fprintf(stderr, "no mem for next token\n"); err_ret->error = E_NOMEM; break; } if (len > 0) strncpy(str, a, len); str[len] = '\0'; #ifdef PY_PARSER_REQUIRES_FUTURE_KEYWORD /* This is only necessary to support the "as" warning, but we don't want to warn about "as" in import statements. */ if (type == NAME && len == 6 && str[0] == 'i' && strcmp(str, "import") == 0) handling_import = 1; /* Warn about with as NAME */ if (type == NAME && !(ps->p_flags & CO_FUTURE_WITH_STATEMENT)) { if (len == 4 && str[0] == 'w' && strcmp(str, "with") == 0) warn(with_msg, err_ret->filename, tok->lineno); else if (!(handling_import || handling_with) && len == 2 && str[0] == 'a' && strcmp(str, "as") == 0) warn(as_msg, err_ret->filename, tok->lineno); } else if (type == NAME && (ps->p_flags & CO_FUTURE_WITH_STATEMENT) && len == 4 && str[0] == 'w' && strcmp(str, "with") == 0) handling_with = 1; #endif if (a >= tok->line_start) col_offset = a - tok->line_start; else col_offset = -1; if ((err_ret->error = PyParser_AddToken(ps, (int)type, str, tok->lineno, col_offset, &(err_ret->expected))) != E_OK) { if (err_ret->error != E_DONE) { PyObject_FREE(str); err_ret->token = type; } break; } } if (err_ret->error == E_DONE) { n = ps->p_tree; ps->p_tree = NULL; } else n = NULL; PyParser_Delete(ps); if (n == NULL) { if (tok->lineno <= 1 && tok->done == E_EOF) err_ret->error = E_EOF; err_ret->lineno = tok->lineno; if (tok->buf != NULL) { size_t len; assert(tok->cur - tok->buf < INT_MAX); err_ret->offset = (int)(tok->cur - tok->buf); len = tok->inp - tok->buf; err_ret->text = (char *) PyObject_MALLOC(len + 1); if (err_ret->text != NULL) { if (len > 0) strncpy(err_ret->text, tok->buf, len); err_ret->text[len] = '\0'; } } } else if (tok->encoding != NULL) { node* r = PyNode_New(encoding_decl); if (!r) { err_ret->error = E_NOMEM; n = NULL; goto done; } r->n_str = tok->encoding; r->n_nchildren = 1; r->n_child = n; tok->encoding = NULL; n = r; } done: PyTokenizer_Free(tok); return n; } static void initerr(perrdetail *err_ret, const char *filename) { err_ret->error = E_OK; err_ret->filename = filename; err_ret->lineno = 0; err_ret->offset = 0; err_ret->text = NULL; err_ret->token = -1; err_ret->expected = -1; }