parser.c@87e3bb5086e8
parser.c
Mon, 20 Apr 2020 10:14:32 -0500
- author
- Tuomo Valkonen <tuomov@iki.fi>
- date
- Mon, 20 Apr 2020 10:14:32 -0500
- changeset 119
- 87e3bb5086e8
- parent 70
- e866dc825481
- permissions
- -rw-r--r--
Convert README to markdown
/* * libtu/parser.c * * Copyright (c) Tuomo Valkonen 1999-2002. * * You may distribute and modify this library under the terms of either * the Clarified Artistic License or the GNU LGPL, version 2.1 or later. */ #include <string.h> #include <errno.h> #include "parser.h" #include "misc.h" #include "output.h" #define MAX_TOKENS 256 #define MAX_NEST 256 enum{ P_NONE=1, P_EOF, P_STMT, P_STMT_NS, P_STMT_SECT, P_BEG_SECT, P_END_SECT }; /* */ static bool opt_include(Tokenizer *tokz, int n, Token *toks); static ConfOpt common_opts[]={ {"include", "s", opt_include, NULL}, {NULL, NULL, NULL, NULL} }; /* */ static int read_statement(Tokenizer *tokz, Token *tokens, int *ntok_ret) { int ntokens=0; Token *tok=NULL; int had_comma=0; /* 0 - no, 1 - yes, 2 - not had, not expected */ int retval=0; int e=0; while(1){ tok=&tokens[ntokens]; if(!tokz_get_token(tokz, tok)){ e=1; continue; } if(ntokens==MAX_TOKENS-1){ e=E_TOKZ_TOKEN_LIMIT; tokz_warn_error(tokz, tok->line, e); if(!(tokz->flags&TOKZ_ERROR_TOLERANT)) break; }else{ ntokens++; } if(!TOK_IS_OP(tok)){ if(ntokens==1 && !had_comma){ /* first token */ had_comma=2; }else{ if(had_comma==0) goto syntax; had_comma=0; } continue; } /* It is an operator */ ntokens--; switch(TOK_OP_VAL(tok)){ case OP_SCOLON: retval=(ntokens==0 ? P_NONE : P_STMT_NS); break; case OP_NEXTLINE: retval=(ntokens==0 ? P_NONE : P_STMT); break; case OP_L_BRC: retval=(ntokens==0 ? P_BEG_SECT : P_STMT_SECT); break; case OP_R_BRC: if(ntokens==0){ retval=P_END_SECT; }else{ tokz_unget_token(tokz, tok); retval=P_STMT_NS; } break; case OP_EOF: retval=(ntokens==0 ? P_EOF : P_STMT_NS); if(had_comma==1){ e=E_TOKZ_UNEXPECTED_EOF; goto handle_error; } goto end; case OP_COMMA: if(had_comma!=0) goto syntax; had_comma=1; continue; default: goto syntax; } if(had_comma!=1) break; syntax: e=E_TOKZ_SYNTAX; handle_error: tokz_warn_error(tokz, tok->line, e); if(!(tokz->flags&TOKZ_ERROR_TOLERANT) || retval!=0) break; } end: if(e!=0) retval=-retval; *ntok_ret=ntokens; return retval; } static bool find_beg_sect(Tokenizer *tokz) { Token tok=TOK_INIT; while(tokz_get_token(tokz, &tok)){ if(TOK_IS_OP(&tok)){ if(TOK_OP_VAL(&tok)==OP_NEXTLINE) continue; if(TOK_OP_VAL(&tok)==OP_SCOLON) return FALSE; if(TOK_OP_VAL(&tok)==OP_L_BRC) return TRUE; } tokz_unget_token(tokz, &tok); break; } return FALSE; } /* */ static const ConfOpt* lookup_option(const ConfOpt *opts, const char *name) { while(opts->optname!=NULL){ if(strcmp(opts->optname, name)==0) return opts; opts++; } return NULL; } static bool call_end_sect(Tokenizer *tokz, const ConfOpt *opts) { opts=lookup_option(opts, "#end"); if(opts!=NULL) return opts->fn(tokz, 0, NULL); return TRUE; } static bool call_cancel_sect(Tokenizer *tokz, const ConfOpt *opts) { opts=lookup_option(opts, "#cancel"); if(opts!=NULL) return opts->fn(tokz, 0, NULL); return TRUE; } /* */ bool parse_config_tokz(Tokenizer *tokz, const ConfOpt *options) { Token tokens[MAX_TOKENS]; bool alloced_optstack=FALSE; int i, t, ntokens=0; int init_nest_lvl; bool had_error; int errornest=0; bool is_default=FALSE; /* Allocate tokz->optstack if it does not yet exist (if it does, * we have been called from an option handler) */ if(!tokz->optstack){ tokz->optstack=ALLOC_N(const ConfOpt*, MAX_NEST); if(!tokz->optstack){ warn_err(); return FALSE; } memset(tokz->optstack, 0, sizeof(ConfOpt*)*MAX_NEST); init_nest_lvl=tokz->nest_lvl=0; alloced_optstack=TRUE; }else{ init_nest_lvl=tokz->nest_lvl; } tokz->optstack[init_nest_lvl]=options; for(i=0; i<MAX_TOKENS; i++) tok_init(&tokens[i]); while(1){ had_error=FALSE; /* free the tokens */ while(ntokens--) tok_free(&tokens[ntokens]); /* read the tokens */ t=read_statement(tokz, tokens, &ntokens); if((had_error=t<0)) t=-t; switch(t){ case P_STMT: case P_STMT_NS: case P_STMT_SECT: if(errornest) had_error=TRUE; else if(tokz->flags&TOKZ_PARSER_INDENT_MODE) verbose_indent(tokz->nest_lvl); if(!TOK_IS_IDENT(tokens+0)){ had_error=TRUE; tokz_warn_error(tokz, tokens->line, E_TOKZ_IDENTIFIER_EXPECTED); } if(t==P_STMT){ if(find_beg_sect(tokz)) t=P_STMT_SECT; } if(had_error) break; /* Got the statement and its type */ options=lookup_option(tokz->optstack[tokz->nest_lvl], TOK_IDENT_VAL(tokens+0)); if(options==NULL) options=lookup_option(common_opts, TOK_IDENT_VAL(tokens+0)); if(options==NULL && (tokz->flags&TOKZ_DEFAULT_OPTION)){ options=lookup_option(tokz->optstack[tokz->nest_lvl], "#default"); is_default=(options!=NULL); } if(options==NULL){ had_error=TRUE; tokz_warn_error(tokz, tokens->line, E_TOKZ_UNKNOWN_OPTION); }else if(!is_default) { had_error=!check_args(tokz, tokens, ntokens, options->argfmt); } if(had_error) break; /* Found the option and arguments are ok */ if(options->opts!=NULL){ if(t!=P_STMT_SECT){ had_error=TRUE; tokz_warn_error(tokz, tokz->line, E_TOKZ_LBRACE_EXPECTED); }else if(tokz->nest_lvl==MAX_NEST-1){ tokz_warn_error(tokz, tokz->line, E_TOKZ_MAX_NEST); had_error=TRUE; }else{ tokz->nest_lvl++; tokz->optstack[tokz->nest_lvl]=options->opts; } }else if(t==P_STMT_SECT){ had_error=TRUE; tokz_warn_error(tokz, tokz->line, E_TOKZ_SYNTAX); } if(!had_error && options->fn!=NULL){ had_error=!options->fn(tokz, ntokens, tokens); if(t==P_STMT_SECT && had_error) tokz->nest_lvl--; } break; case P_EOF: if(tokz_popf(tokz)){ break; }else if(tokz->nest_lvl>0 || errornest>0){ tokz_warn_error(tokz, 0, E_TOKZ_UNEXPECTED_EOF); had_error=TRUE; } goto eof; case P_BEG_SECT: had_error=TRUE; errornest++; tokz_warn_error(tokz, tokz->line, E_TOKZ_SYNTAX); break; case P_END_SECT: if(tokz->nest_lvl+errornest==0){ tokz_warn_error(tokz, tokz->line, E_TOKZ_SYNTAX); had_error=TRUE; } if(had_error) break; if(errornest!=0){ errornest--; }else{ had_error=!call_end_sect(tokz, tokz->optstack[tokz->nest_lvl]); tokz->nest_lvl--; } if(tokz->nest_lvl<init_nest_lvl) goto eof; } if(!had_error) continue; if(t==P_STMT_SECT) errornest++; if(!(tokz->flags&TOKZ_ERROR_TOLERANT)) break; } eof: /* free the tokens */ while(ntokens--) tok_free(&tokens[ntokens]); while(tokz->nest_lvl>=init_nest_lvl){ if(tokz->flags&TOKZ_ERROR_TOLERANT || !had_error) call_end_sect(tokz, tokz->optstack[tokz->nest_lvl]); else call_cancel_sect(tokz, tokz->optstack[tokz->nest_lvl]); tokz->nest_lvl--; } /* Free optstack if it was alloced by this call */ if(alloced_optstack){ free(tokz->optstack); tokz->optstack=NULL; tokz->nest_lvl=0; } if(tokz->flags&TOKZ_PARSER_INDENT_MODE) verbose_indent(init_nest_lvl); return !had_error; } /* */ bool parse_config(const char *fname, const ConfOpt *options, int flags) { Tokenizer *tokz; bool ret; tokz=tokz_open(fname); if(tokz==NULL) return FALSE; tokz->flags|=flags&~TOKZ_READ_COMMENTS; ret=parse_config_tokz(tokz, options); tokz_close(tokz); return ret; } bool parse_config_file(FILE *file, const ConfOpt *options, int flags) { Tokenizer *tokz; bool ret; tokz=tokz_open_file(file, NULL); if(tokz==NULL) return FALSE; tokz->flags|=flags&~TOKZ_READ_COMMENTS; ret=parse_config_tokz(tokz, options); tokz_close(tokz); return ret; } /* * Argument validity checking stuff */ static int arg_match(Token *tok, char c, bool si) { char c2=tok->type; if(c=='.' || c=='*') return 0; if(c2==c) return 0; if(si){ if(c2=='i' && c=='s'){ TOK_SET_IDENT(tok, TOK_STRING_VAL(tok)); return 0; } if(c2=='s' && c=='i'){ TOK_SET_STRING(tok, TOK_IDENT_VAL(tok)); return 0; } } if(c2=='c' && c=='l'){ TOK_SET_LONG(tok, TOK_CHAR_VAL(tok)); return 0; } if(c2=='l' && c=='c'){ TOK_SET_CHAR(tok, TOK_LONG_VAL(tok)); return 0; } if(c2=='l' && c=='d'){ TOK_SET_DOUBLE(tok, TOK_LONG_VAL(tok)); return 0; } if(c=='b'){ if(c2=='l'){ TOK_SET_BOOL(tok, TOK_LONG_VAL(tok)); return 0; }else if(c2=='i'){ if(strcmp(TOK_IDENT_VAL(tok), "TRUE")==0){ tok_free(tok); TOK_SET_BOOL(tok, TRUE); return 0; }else if(strcmp(TOK_IDENT_VAL(tok), "FALSE")==0){ tok_free(tok); TOK_SET_BOOL(tok, FALSE); return 0; } } } return E_TOKZ_INVALID_ARGUMENT; } static int check_argument(const char **pret, Token *tok, const char *p, bool si) { int mode; int e=E_TOKZ_TOO_MANY_ARGS; again: mode=0; if(*p=='*'){ *pret=p; return 0; }else if(*p=='?'){ mode=1; p++; }else if(*p==':'){ mode=2; p++; }else if(*p=='+'){ *pret=p; return arg_match(tok, *(p-1), si); } while(*p!='\0'){ e=arg_match(tok, *p, si); if(e==0){ p++; while(mode==2 && *p==':'){ if(*++p=='\0') break; /* Invalid argument format string, though... */ p++; } *pret=p; return 0; } if(mode==0) break; p++; if(mode==1) goto again; /* mode==2 */ if(*p!=':') break; p++; e=E_TOKZ_TOO_MANY_ARGS; } *pret=p; return e; } static bool args_at_end(const char *p) { if(p==NULL) return TRUE; while(*p!='\0'){ if(*p=='*' || *p=='+') p++; else if(*p=='?') p+=2; else return FALSE; } return TRUE; } bool do_check_args(const Tokenizer *tokz, Token *tokens, int ntokens, const char *fmt, bool si) { int i; int e; if(fmt==NULL){ if(ntokens!=1) tokz_warn_error(tokz, tokens[0].line, E_TOKZ_TOO_MANY_ARGS); return ntokens==1; } for(i=1; i<ntokens; i++){ e=check_argument(&fmt, &tokens[i], fmt, si); if(e!=0){ tokz_warn_error(tokz, tokens[i].line, e); return FALSE; } } if(!args_at_end(fmt)){ tokz_warn_error(tokz, tokens[i].line, E_TOKZ_TOO_FEW_ARGS); return FALSE; } return TRUE; } bool check_args(const Tokenizer *tokz, Token *tokens, int ntokens, const char *fmt) { return do_check_args(tokz, tokens, ntokens, fmt, FALSE); } bool check_args_loose(const Tokenizer *tokz, Token *tokens, int ntokens, const char *fmt) { return do_check_args(tokz, tokens, ntokens, fmt, TRUE); } /* */ static bool try_include(Tokenizer *tokz, const char *fname) { FILE *f; f=fopen(fname, "r"); if(f==NULL) return FALSE; if(!tokz_pushf_file(tokz, f, fname)){ fclose(f); return FALSE; } return TRUE; } static bool try_include_dir(Tokenizer *tokz, const char *dir, int dlen, const char *file) { char *tmpname; bool retval; tmpname=scatn(dir, dlen, file, -1); if(tmpname==NULL){ warn_err(); return FALSE; } retval=try_include(tokz, tmpname); free(tmpname); return retval; } static bool opt_include(Tokenizer *tokz, int n, Token *toks) { const char *fname=TOK_STRING_VAL(toks+1); const char *lastndx=NULL; bool retval, e; int i=0; if(fname[0]!='/' && tokz->name!=NULL) lastndx=strrchr(tokz->name, '/'); if(lastndx==NULL) retval=try_include(tokz, fname); else retval=try_include_dir(tokz, tokz->name, lastndx-tokz->name+1, fname); if(retval==TRUE) return TRUE; e=errno; if(tokz->includepaths!=NULL){ while(tokz->includepaths[i]!=NULL){ if(try_include_dir(tokz, tokz->includepaths[i], -1, fname)) return TRUE; i++; } } warn_obj(fname, "%s", strerror(e)); return FALSE; } extern void tokz_set_includepaths(Tokenizer *tokz, char **paths) { tokz->includepaths=paths; } ConfOpt libtu_dummy_confopts[]={ END_CONFOPTS }; bool parse_config_tokz_skip_section(Tokenizer *tokz) { return parse_config_tokz(tokz, libtu_dummy_confopts); }
