# -*- Autoconf -*- cat < #include #include ]$4[ static int power (int base, int exponent); static void yyerror (const char *s); static int yylex (void); extern void perror (const char *s); %} /* BISON Declarations */ %token NUM %nonassoc '=' /* comparison */ %left '-' '+' %left '*' '/' %left NEG /* negation--unary minus */ %right '^' /* exponentiation */ /* Grammar follows */ %% input: /* empty string */ | input line ; line: '\n' | exp '\n' ; exp: NUM { $$ = $1; } | exp '=' exp { if ($1 != $3) printf ("calc: error: %d != %d\n", $1, $3); $$ = $1 == $3; } | exp '+' exp { $$ = $1 + $3; } | exp '-' exp { $$ = $1 - $3; } | exp '*' exp { $$ = $1 * $3; } | exp '/' exp { $$ = $1 / $3; } | '-' exp %prec NEG { $$ = -$2; } | exp '^' exp { $$ = power ($1, $3); } | '(' exp ')' { $$ = $2; } ; %% /* The input. */ FILE *yyin; static void yyerror (const char *s) { #if YYLSP_NEEDED fprintf (stderr, "%d.%d:%d.%d: ", yylloc.first_line, yylloc.first_column, yylloc.last_line, yylloc.last_column); #endif fprintf (stderr, "%s\n", s); } static int yygetc () { int res = getc (yyin); #if YYLSP_NEEDED if (res == '\n') { yylloc.last_line++; yylloc.last_column = 0; } else yylloc.last_column++; #endif return res; } static void yyungetc (int c) { #if YYLSP_NEEDED /* Wrong when C == `\n'. */ yylloc.last_column--; #endif ungetc (c, yyin); } static int read_signed_integer (void) { int c = yygetc (); int sign = 1; int n = 0; if (c == '-') { c = yygetc (); sign = -1; } while (isdigit (c)) { n = 10 * n + (c - '0'); c = yygetc (); } yyungetc (c); return sign * n; } /*---------------------------------------------------------------. | Lexical analyzer returns an integer on the stack and the token | | NUM, or the ASCII character read if not a number. Skips all | | blanks and tabs, returns 0 for EOF. | `---------------------------------------------------------------*/ static int yylex (void) { int c; #if YYLSP_NEEDED yylloc.first_column = yylloc.last_column; yylloc.first_line = yylloc.last_line; #endif /* Skip white space. */ while ((c = yygetc ()) == ' ' || c == '\t') { #if YYLSP_NEEDED yylloc.first_column = yylloc.last_column; yylloc.first_line = yylloc.last_line; #endif } /* process numbers */ if (c == '.' || isdigit (c)) { yyungetc (c); yylval = read_signed_integer (); return NUM; } /* Return end-of-file. */ if (c == EOF) return 0; /* Return single chars. */ return c; } static int power (int base, int exponent) { int res = 1; if (exponent < 0) exit (1); for (/* Niente */; exponent; --exponent) res *= base; return res; } int main (int argn, const char **argv) { if (argn == 2) yyin = fopen (argv[1], "r"); else yyin = stdin; if (!stdin) { perror (argv[1]); exit (1); } #if YYDEBUG yydebug = 1; #endif #if YYLSP_NEEDED yylloc.last_column = 0; yylloc.last_line = 1; #endif yyparse (); return 0; } ]]) ])# _AT_DATA_CALC_Y # AT_DATA_CALC_Y([BISON-OPTIONS]) # ------------------------------- # Produce `calc.y'. AT_DEFINE([AT_DATA_CALC_Y], [_AT_DATA_CALC_Y($[1], $[2], $[3], [ifelse(regexp([$1], [--yyerror-verbose]), [-1], [], [[#define YYERROR_VERBOSE]])])]) # _AT_CHECK_CALC(BISON-OPTIONS, INPUT) # ------------------------------------ # Run `calc' on INPUT and expect no STDOUT nor STDERR. # If `--debug' is passed to bison, discard all the debugging traces # preserving only the `parse errors'. Note that since there should be # none, the `grep' will fail with exit status 1. AT_DEFINE([_AT_CHECK_CALC], [ifelse(regexp([$1], [--debug]), [-1], [AT_CHECK([echo "$2" | calc], [0], [], [])], [AT_CHECK([echo "$2" | calc 2>&1 >/dev/null | grep 'parse error' >&2], [1], [], [])])]) # _AT_CHECK_CALC_ERROR(BISON-OPTIONS, INPUT, # [ERROR-LOCATION], [IF-YYERROR-VERBOSE]) # ------------------------------------------------------------ # Run `calc' on INPUT, and expect STDERR. AT_DEFINE([_AT_CHECK_CALC_ERROR], [AT_CHECK([echo "$2" | calc 2>&1 >/dev/null | grep 'parse error' >&2], 0, [], [ifelse(regexp([$1], [--location]), [-1], [], [$3: ])[]dnl parse error[]dnl ifelse(regexp([$1], [--yyerror-verbose]), [-1], [], [$4])[]dnl ])]) # AT_CHECK_CALC([BISON-OPTIONS], [PARSER-EXPECTED-STDERR]) # -------------------------------------------------------- # Start a testing chunk which compiles `calc' grammar with # BISON-OPTIONS, and performs several tests over the parser. AT_DEFINE([AT_CHECK_CALC], [# We use integers to avoid dependencies upon the precision of doubles. AT_SETUP([Calculator $1]) AT_DATA_CALC_Y([$1]) # Specify the output files to avoid problems on different file systems. AT_CHECK([bison calc.y -o calc.c patsubst([$1], [--yyerror-verbose])], [0], [], []) AT_CHECK([$CC $CFLAGS calc.c -o calc], 0, [], []) # Test the priorities. _AT_CHECK_CALC([$1], [1 + 2 * 3 = 7 1 + 2 * -3 = -5 -1^2 = -1 (-1)^2 = 1 ---1 = -1 1 - 2 - 3 = -4 1 - (2 - 3) = 2 2^2^3 = 256 (2^2)^3 = 64], [$2]) # Some parse errors. _AT_CHECK_CALC_ERROR([$1], [+1], [1.0:1.1], [, unexpected `'+'']) _AT_CHECK_CALC_ERROR([$1], [1//2], [1.2:1.3], [, unexpected `'/'', expecting `NUM' or `'-'' or `'('']) _AT_CHECK_CALC_ERROR([$1], [error], [1.0:1.1], [, unexpected `$undefined.']) _AT_CHECK_CALC_ERROR([$1], [1 = 2 = 3], [1.6:1.7], [, unexpected `'='']) _AT_CHECK_CALC_ERROR([$1], [ +1], [2.0:2.1], [, unexpected `'+'']) AT_CLEANUP(calc calc.c calc.h calc.output) ])# AT_CHECK_CALC # ------------------ # # Test the parsers. # # ------------------ # AT_CHECK_CALC() AT_CHECK_CALC([--defines]) AT_CHECK_CALC([--locations]) AT_CHECK_CALC([--name-prefix=calc]) AT_CHECK_CALC([--verbose]) AT_CHECK_CALC([--yacc]) AT_CHECK_CALC([--yyerror-verbose]) AT_CHECK_CALC([--locations --yyerror-verbose]) AT_CHECK_CALC([--defines --locations --name-prefix=calc --verbose --yacc --yyerror-verbose]) AT_CHECK_CALC([--debug]) AT_CHECK_CALC([--debug --defines --locations --name-prefix=calc --verbose --yacc --yyerror-verbose])