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testlang_parse.y revision 1.8
      1 %{
      2 /*	$NetBSD: testlang_parse.y,v 1.8 2011/08/18 02:44:45 christos Exp $	*/
      3 
      4 /*-
      5  * Copyright 2009 Brett Lymn <blymn (at) NetBSD.org>
      6  *
      7  * All rights reserved.
      8  *
      9  * This code has been donated to The NetBSD Foundation by the Author.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. The name of the author may not be used to endorse or promote products
     17  *    derived from this software withough specific prior written permission
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29  *
     30  *
     31  */
     32 #include <assert.h>
     33 #include <errno.h>
     34 #include <fcntl.h>
     35 #include <err.h>
     36 #include <unistd.h>
     37 #include <poll.h>
     38 #include <stdbool.h>
     39 #include <stdio.h>
     40 #include <string.h>
     41 #include <sys/syslimits.h>
     42 #include <time.h>
     43 #include <vis.h>
     44 #include "returns.h"
     45 
     46 #define YYDEBUG 1
     47 
     48 extern int verbose;
     49 extern int cmdpipe[2];
     50 extern int slvpipe[2];
     51 extern int master;
     52 extern struct pollfd readfd;
     53 extern char *check_path;
     54 extern char *cur_file;		/* from director.c */
     55 
     56 int yylex(void);
     57 
     58 size_t line;
     59 
     60 static int input_delay;
     61 
     62 /* time delay between inputs chars - default to 0.1ms minimum to prevent
     63  * problems with input tests
     64  */
     65 #define DELAY_MIN 0.1
     66 static struct timespec delay_spec = {0, 1000 * DELAY_MIN};
     67 static char *input_str;	/* string to feed in as input */
     68 static bool no_input;	/* don't need more input */
     69 
     70 #define READ_PIPE  0
     71 #define WRITE_PIPE 1
     72 
     73 const char *returns_enum_names[] = {
     74 	"unused", "numeric", "string", "byte", "ERR", "OK", "NULL", "not NULL",
     75 	"variable", "reference", "returns count", "slave error"
     76 };
     77 
     78 typedef enum {
     79 	arg_static,
     80 	arg_byte,
     81 	arg_var,
     82 	arg_null
     83 } args_state_t;
     84 
     85 static const char *args_enum_names[] = {
     86 	"static", "byte", "var", "NULL"
     87 };
     88 
     89 typedef struct {
     90 	args_state_t	arg_type;
     91 	size_t		arg_len;
     92 	char		*arg_string;
     93 	int		var_index;
     94 } args_t;
     95 
     96 typedef struct {
     97 	char		*function;
     98 	int		nrets;		/* number of returns */
     99 	returns_t	*returns;	/* array of expected returns */
    100 	int		nargs;		/* number of arguments */
    101 	args_t		*args;		/* arguments for the call */
    102 } cmd_line_t;
    103 
    104 static cmd_line_t	command;
    105 
    106 typedef struct {
    107 	char *name;
    108 	size_t len;
    109 	returns_enum_t type;
    110 	void *value;
    111 } var_t;
    112 
    113 static size_t nvars; 		/* Number of declared variables */
    114 static var_t *vars; 		/* Variables defined during the test. */
    115 
    116 static int	check_function_table(char *, const char *[], int);
    117 static int	find_var_index(const char *);
    118 static void 	assign_arg(args_state_t, void *);
    119 static int	assign_var(char *);
    120 void		init_parse_variables(int);
    121 static void	validate(int, void *);
    122 static void	validate_return(const char *, const char *, int);
    123 static void	validate_variable(int, returns_enum_t, const void *, int, int);
    124 static void	validate_byte(returns_t *, returns_t *, int);
    125 static void	write_cmd_pipe(char *);
    126 static void	write_cmd_pipe_args(args_state_t, void *);
    127 static void	read_cmd_pipe(returns_t *);
    128 static void	write_func_and_args(void);
    129 static void	compare_streams(char *, bool);
    130 static void	do_function_call(size_t);
    131 static void	save_slave_output(bool);
    132 static void	validate_type(returns_enum_t, returns_t *, int);
    133 static void	set_var(returns_enum_t, char *, void *);
    134 static void	validate_reference(int, void *);
    135 static char	*numeric_or(char *, char *);
    136 static char	*get_numeric_var(const char *);
    137 
    138 static const char *input_functions[] = {
    139 	"inch", "getch", "getnstr", "getstr", "innstr", "instr", "mvgetnstr",
    140 	"mvgetstr", "mvinchstr", "mvinchnstr", "mvgetnstr", "mvgetstr",
    141 	"mvinchstr", "mvinchnstr", "winch", "wgetch", "wgetnstr", "wgetstr",
    142 	"winchnstr", "winchstr", "winnstr", "winstr"
    143 };
    144 
    145 static const unsigned ninput_functions =
    146 	sizeof(input_functions) / sizeof(char *);
    147 
    148 saved_data_t saved_output;
    149 
    150 %}
    151 
    152 %union {
    153 	char *string;
    154 	returns_t *retval;
    155 }
    156 
    157 %token <string> PATH
    158 %token <string> STRING
    159 %token <retval> BYTE
    160 %token <string> VARNAME
    161 %token <string> FILENAME
    162 %token <string> VARIABLE
    163 %token <string> REFERENCE
    164 %token <string> NULL_RET
    165 %token <string> NON_NULL
    166 %token <string> ERR_RET
    167 %token <string> OK_RET
    168 %token <string> numeric
    169 %token <string> DELAY
    170 %token <string> INPUT
    171 %token <string> COMPARE
    172 %token <string> COMPAREND
    173 %token <string> ASSIGN
    174 %token EOL CALL CHECK NOINPUT OR LHB RHB
    175 %token CALL2 CALL3 CALL4 DRAIN
    176 
    177 %nonassoc OR
    178 
    179 %%
    180 
    181 statement	:	/* empty */
    182 		| assign statement
    183 		| call statement
    184 		| call2 statement
    185 		| call3 statement
    186 		| call4 statement
    187 		| check statement
    188 		| delay statement
    189 		| input statement
    190 		| noinput statement
    191 		| compare statement
    192 		| comparend statement
    193 		| eol statement
    194 		;
    195 
    196 assign		: ASSIGN VARNAME numeric {set_var(ret_number, $2, $3);} eol
    197 		| ASSIGN VARNAME LHB expr RHB {set_var(ret_number, $2, $<string>4);} eol
    198 		| ASSIGN VARNAME STRING {set_var(ret_string, $2, $3);} eol
    199 		| ASSIGN VARNAME BYTE {set_var(ret_byte, $2, $3);} eol
    200 		;
    201 
    202 call		: CALL result fn_name args eol {
    203 	do_function_call(1);
    204 }
    205 		;
    206 
    207 call2		: CALL2 result result fn_name args eol {
    208 	do_function_call(2);
    209 }
    210 		;
    211 
    212 call3		: CALL3 result result result fn_name args eol {
    213 	do_function_call(3);
    214 }
    215 		;
    216 
    217 call4		: CALL4 result result result result fn_name args eol {
    218 	do_function_call(4);
    219  }
    220 		;
    221 
    222 check		: CHECK var returns eol {
    223 	returns_t retvar;
    224 	var_t *vptr;
    225 	if (command.returns[0].return_index == -1)
    226 		err(1, "Undefined variable in check statement, line %zu"
    227 		    " of file %s", line, cur_file);
    228 
    229 	if (verbose)
    230 		fprintf(stderr, "Checking contents of variable %s for %s\n",
    231 		    vars[command.returns[0].return_index].name,
    232 		    returns_enum_names[command.returns[1].return_type]);
    233 
    234 	if (((command.returns[1].return_type == ret_byte) &&
    235 	     (vars[command.returns[0].return_index].type != ret_byte)) ||
    236 	    vars[command.returns[0].return_index].type != ret_string)
    237 		err(1, "Var type %s (%d) does not match return type %s (%d)",
    238 		    returns_enum_names[vars[command.returns[0].return_index].type],
    239 		    vars[command.returns[0].return_index].type,
    240 		    returns_enum_names[command.returns[1].return_type],
    241 		    command.returns[1].return_type);
    242 
    243 	switch (command.returns[1].return_type) {
    244 	case ret_err:
    245 		validate_variable(0, ret_string, "ERR",
    246 				  command.returns[0].return_index, 0);
    247 		break;
    248 
    249 	case ret_ok:
    250 		validate_variable(0, ret_string, "OK",
    251 				  command.returns[0].return_index, 0);
    252 		break;
    253 
    254 	case ret_null:
    255 		validate_variable(0, ret_string, "NULL",
    256 				  command.returns[0].return_index, 0);
    257 		break;
    258 
    259 	case ret_nonnull:
    260 		validate_variable(0, ret_string, "NULL",
    261 				  command.returns[0].return_index, 1);
    262 		break;
    263 
    264 	case ret_string:
    265 	case ret_number:
    266 		if (verbose)
    267 			fprintf(stderr, " %s == returned %s\n",
    268 			    (const char *)command.returns[1].return_value,
    269 			    (const char *)
    270 			    vars[command.returns[0].return_index].value);
    271 		validate_variable(0, ret_string,
    272 		    command.returns[1].return_value,
    273 		    command.returns[0].return_index, 0);
    274 		break;
    275 
    276 	case ret_byte:
    277 		vptr = &vars[command.returns[0].return_index];
    278 		retvar.return_len = vptr->len;
    279 		retvar.return_type = vptr->type;
    280 		retvar.return_value = vptr->value;
    281 		validate_byte(&retvar, &command.returns[1], 0);
    282 		break;
    283 
    284 	default:
    285 		err(1, "Malformed check statement at line %zu "
    286 		    "of file %s", line, cur_file);
    287 		break;
    288 	}
    289 
    290 	init_parse_variables(0);
    291  }
    292 		;
    293 
    294 delay		: DELAY numeric eol {
    295 	/* set the inter-character delay */
    296 	if (sscanf($2, "%d", &input_delay) == 0)
    297 		err(1, "delay specification %s could not be converted to "
    298 		    "numeric at line %zu of file %s", $2, line, cur_file);
    299 	if (verbose)
    300 		fprintf(stderr, "Set input delay to %d ms\n", input_delay);
    301 
    302 	if (input_delay < DELAY_MIN)
    303 		input_delay = 1000 * DELAY_MIN; /* ms to ns */
    304 	/*
    305 	 * Fill in the timespec structure now ready for use later.
    306 	 * The delay is specified in milliseconds so convert to timespec
    307 	 * values
    308 	 */
    309 	delay_spec.tv_sec = input_delay / 1000;
    310 	delay_spec.tv_nsec = (input_delay - 1000 * delay_spec.tv_sec) * 1000;
    311 
    312 	init_parse_variables(0);
    313  }
    314 	;
    315 
    316 input		: INPUT STRING eol {
    317 	if (input_str != NULL) {
    318 		warnx("%s, %zu: Discarding unused input string",
    319 		    cur_file, line);
    320 		free(input_str);
    321 	}
    322 
    323 	if ((input_str = malloc(strlen($2) + 1)) == NULL)
    324 		err(2, "Cannot allocate memory for input string");
    325 
    326 	strlcpy(input_str, $2, strlen($2) + 1);
    327 }
    328 	;
    329 
    330 
    331 noinput		: NOINPUT eol {
    332 	if (input_str != NULL) {
    333 		warnx("%s, %zu: Discarding unused input string",
    334 		    cur_file, line);
    335 		free(input_str);
    336 	}
    337 
    338 	no_input = true;
    339  }
    340 
    341 compare		: COMPARE PATH eol
    342 		| COMPARE FILENAME eol
    343 {
    344 	compare_streams($2, true);
    345 }
    346 	;
    347 
    348 
    349 comparend	: COMPAREND PATH eol
    350 		| COMPAREND FILENAME eol
    351 {
    352 	compare_streams($2, false);
    353 }
    354 	;
    355 
    356 
    357 result		: returns
    358 		| var
    359 		| reference
    360 		;
    361 
    362 returns		: numeric { assign_rets(ret_number, $1); }
    363 		| LHB expr RHB { assign_rets(ret_number, $<string>2); }
    364 		| STRING { assign_rets(ret_string, $1); }
    365 		| BYTE { assign_rets(ret_byte, (void *) $1); }
    366 		| ERR_RET { assign_rets(ret_err, NULL); }
    367 		| OK_RET { assign_rets(ret_ok, NULL); }
    368 		| NULL_RET { assign_rets(ret_null, NULL); }
    369 		| NON_NULL { assign_rets(ret_nonnull, NULL); }
    370 		;
    371 
    372 var		: VARNAME {
    373 	assign_rets(ret_var, $1);
    374  }
    375 		;
    376 
    377 reference	: VARIABLE {
    378 	assign_rets(ret_ref, $1);
    379  }
    380 
    381 fn_name		: VARNAME {
    382 	if (command.function != NULL)
    383 		free(command.function);
    384 
    385 	command.function = malloc(strlen($1) + 1);
    386 	if (command.function == NULL)
    387 		err(1, "Could not allocate memory for function name");
    388 	strcpy(command.function, $1);
    389  }
    390 		;
    391 
    392 expr		: numeric
    393 		| VARIABLE
    394 			{ $<string>$ = get_numeric_var($1); }
    395 		| expr OR expr
    396 			{ $<string>$ = numeric_or($<string>1, $<string>3); }
    397 		;
    398 
    399 args		: /* empty */
    400 		| LHB expr RHB { assign_arg(arg_static, $<string>2); } args
    401 		| numeric { assign_arg(arg_static, $1); } args
    402 		| STRING { assign_arg(arg_static, $1); } args
    403 		| BYTE { assign_arg(arg_byte, $1); } args
    404 		| PATH { assign_arg(arg_static, $1); } args
    405 		| FILENAME { assign_arg(arg_static, $1); } args
    406 		| VARNAME { assign_arg(arg_static, $1); } args
    407 		| VARIABLE  { assign_arg(arg_var, $1); } args
    408 		| NULL_RET { assign_arg(arg_null, $1); } args
    409 		;
    410 
    411 eol		: EOL
    412 		;
    413 
    414 %%
    415 
    416 static void
    417 excess(const char *fname, size_t lineno, const char *func, const char *comment,
    418     const void *data, size_t datalen)
    419 {
    420 	size_t dstlen = datalen * 4 + 1;
    421 	char *dst = malloc(dstlen);
    422 
    423 	if (dst == NULL)
    424 		err(1, "malloc");
    425 
    426 	if (strnvisx(dst, dstlen, data, datalen, VIS_WHITE | VIS_OCTAL) == -1)
    427 		err(1, "strnvisx");
    428 
    429 	warnx("%s, %zu: [%s] Excess %zu bytes%s [%s]",
    430 	    fname, lineno, func, datalen, comment, dst);
    431 	free(dst);
    432 }
    433 
    434 /*
    435  * Get the value of a variable, error if the variable has not been set or
    436  * is not a numeric type.
    437  */
    438 static char *
    439 get_numeric_var(const char *var)
    440 {
    441 	int i;
    442 
    443 	if ((i = find_var_index(var)) < 0)
    444 		err(1, "Variable %s is undefined", var);
    445 
    446 	if (vars[i].type != ret_number)
    447 		err(1, "Variable %s is not a numeric type", var);
    448 
    449 	return vars[i].value;
    450 }
    451 
    452 /*
    453  * Perform a bitwise OR on two numbers and return the result.
    454  */
    455 static char *
    456 numeric_or(char *n1, char *n2)
    457 {
    458 	unsigned long i1, i2, result;
    459 	char *ret;
    460 
    461 	i1 = strtoul(n1, NULL, 10);
    462 	i2 = strtoul(n2, NULL, 10);
    463 
    464 	result = i1 | i2;
    465 	asprintf(&ret, "%lu", result);
    466 
    467 	if (verbose)
    468 		fprintf(stderr, "numeric or of 0x%lx (%s) and 0x%lx (%s)"
    469 		    " results in 0x%lx (%s)\n",
    470 		    i1, n1, i2, n2, result, ret);
    471 
    472 	return ret;
    473 }
    474 
    475 /*
    476  * Assign the value given to the named variable.
    477  */
    478 static void
    479 set_var(returns_enum_t type, char *name, void *value)
    480 {
    481 	int i;
    482 	char *number;
    483 	returns_t *ret;
    484 
    485 	i = find_var_index(name);
    486 	if (i < 0)
    487 		i = assign_var(name);
    488 
    489 	vars[i].type = type;
    490 	if ((type == ret_number) || (type == ret_string)) {
    491 		number = value;
    492 		vars[i].len = strlen(number) + 1;
    493 		vars[i].value = malloc(vars[i].len + 1);
    494 		if (vars[i].value == NULL)
    495 			err(1, "Could not malloc memory for assign string");
    496 		strcpy(vars[i].value, number);
    497 	} else {
    498 		/* can only be a byte value */
    499 		ret = value;
    500 		vars[i].len = ret->return_len;
    501 		vars[i].value = malloc(vars[i].len);
    502 		if (vars[i].value == NULL)
    503 			err(1, "Could not malloc memory to assign byte string");
    504 		memcpy(vars[i].value, ret->return_value, vars[i].len);
    505 	}
    506 }
    507 
    508 /*
    509  * Add a new variable to the vars array, the value will be assigned later,
    510  * when a test function call returns.
    511  */
    512 static int
    513 assign_var(char *varname)
    514 {
    515 	var_t *temp;
    516 	char *name;
    517 
    518 	if ((name = malloc(strlen(varname) + 1)) == NULL)
    519 		err(1, "Alloc of varname failed");
    520 
    521 	if ((temp = (var_t *) realloc(vars, sizeof(var_t) * (nvars + 1)))
    522 	    == NULL) {
    523 		free(name);
    524 		err(1, "Realloc of vars array failed");
    525 	}
    526 
    527 	strcpy(name, varname);
    528 	vars = temp;
    529 	vars[nvars].name = name;
    530 	vars[nvars].len = 0;
    531 	vars[nvars].value = NULL;
    532 	nvars++;
    533 
    534 	return (nvars - 1);
    535 }
    536 
    537 /*
    538  * Allocate and assign a new argument of the given type.
    539  */
    540 static void
    541 assign_arg(args_state_t arg_type, void *arg)
    542 {
    543 	args_t *temp, cur;
    544 	char *str = arg;
    545 	returns_t *ret;
    546 
    547 	if (verbose)
    548 		printf("function is >%s<, adding arg >%s< type %s\n",
    549 		       command.function, str, args_enum_names[arg_type]);
    550 
    551 	cur.arg_type = arg_type;
    552 	switch (arg_type) {
    553 	case arg_var:
    554 		cur.var_index = find_var_index(arg);
    555 		if (cur.var_index < 0)
    556 			err(1, "Invalid variable %s at line %zu of file %s",
    557 			    str, line, cur_file);
    558 		cur.arg_type = ret_string;
    559 		break;
    560 
    561 	case arg_byte:
    562 		ret = arg;
    563 		cur.arg_len = ret->return_len;
    564 		cur.arg_string = malloc(cur.arg_len);
    565 		if (cur.arg_string == NULL)
    566 			err(1, "Could not malloc memory for arg bytes");
    567 		memcpy(cur.arg_string, ret->return_value, cur.arg_len);
    568 		break;
    569 
    570 	case arg_null:
    571 		cur.arg_len = 0;
    572 		cur.arg_string = NULL;
    573 		break;
    574 
    575 	default:
    576 		cur.arg_len = strlen(str);
    577 		cur.arg_string = malloc(cur.arg_len + 1);
    578 		if (cur.arg_string == NULL)
    579 			err(1, "Could not malloc memory for arg string");
    580 		strcpy(cur.arg_string, arg);
    581 	}
    582 
    583 	temp = realloc(command.args, sizeof(args_t) * (command.nargs + 1));
    584 	if (temp == NULL)
    585 		err(1, "Failed to reallocate args");
    586 	command.args = temp;
    587 	memcpy(&command.args[command.nargs], &cur, sizeof(args_t));
    588 	command.nargs++;
    589 }
    590 
    591 /*
    592  * Allocate and assign a new return.
    593  */
    594 static void
    595 assign_rets(returns_enum_t ret_type, void *ret)
    596 {
    597 	returns_t *temp, cur;
    598 	char *ret_str;
    599 	returns_t *ret_ret;
    600 
    601 	cur.return_type = ret_type;
    602 	if (ret_type != ret_var) {
    603 		if ((ret_type == ret_number) || (ret_type == ret_string)) {
    604 			ret_str = ret;
    605 			cur.return_len = strlen(ret_str) + 1;
    606 			cur.return_value = malloc(cur.return_len + 1);
    607 			if (cur.return_value == NULL)
    608 				err(1,
    609 				    "Could not malloc memory for arg string");
    610 			strcpy(cur.return_value, ret_str);
    611 		} else if (ret_type == ret_byte) {
    612 			ret_ret = ret;
    613 			cur.return_len = ret_ret->return_len;
    614 			cur.return_value = malloc(cur.return_len);
    615 			if (cur.return_value == NULL)
    616 				err(1,
    617 				    "Could not malloc memory for byte string");
    618 			memcpy(cur.return_value, ret_ret->return_value,
    619 			       cur.return_len);
    620 		} else if (ret_type == ret_ref) {
    621 			if ((cur.return_index = find_var_index(ret)) < 0)
    622 				err(1, "Undefined variable reference");
    623 		}
    624 	} else {
    625 		cur.return_index = find_var_index(ret);
    626 		if (cur.return_index < 0)
    627 			cur.return_index = assign_var(ret);
    628 	}
    629 
    630 	temp = realloc(command.returns,
    631 		       sizeof(returns_t) * (command.nrets + 1));
    632 	if (temp == NULL)
    633 		err(1, "Failed to reallocate returns");
    634 	command.returns = temp;
    635 	memcpy(&command.returns[command.nrets], &cur, sizeof(returns_t));
    636 	command.nrets++;
    637 }
    638 
    639 /*
    640  * Find the given variable name in the var array and return the i
    641  * return -1 if var is not found.
    642  */
    643 static int
    644 find_var_index(const char *var_name)
    645 {
    646 	int result;
    647 	size_t i;
    648 
    649 	result = -1;
    650 
    651 	for (i = 0; i < nvars; i++) {
    652 		if (strcmp(var_name, vars[i].name) == 0) {
    653 			result = i;
    654 			break;
    655 		}
    656 	}
    657 
    658 	return result;
    659 }
    660 
    661 /*
    662  * Check the given function name in the given table of names, return 1 if
    663  * there is a match.
    664  */
    665 static int check_function_table(char *function, const char *table[],
    666 				int nfunctions)
    667 {
    668 	int i;
    669 
    670 	for (i = 0; i < nfunctions; i++) {
    671 		if ((strlen(function) == strlen(table[i])) &&
    672 		    (strcmp(function, table[i]) == 0))
    673 			return 1;
    674 	}
    675 
    676 	return 0;
    677 }
    678 
    679 /*
    680  * Compare the output from the slave against the given file and report
    681  * any differences.
    682  */
    683 static void
    684 compare_streams(char *filename, bool discard)
    685 {
    686 	char check_file[PATH_MAX], drain[100], ref, data;
    687 	struct pollfd fds[2];
    688 	int nfd, check_fd;
    689 	ssize_t result;
    690 
    691 	/*
    692 	 * Don't prepend check path iff check file has an absolute
    693 	 * path.
    694 	 */
    695 	if (filename[0] != '/') {
    696 		if (strlcpy(check_file, check_path, sizeof(check_file))
    697 		    >= sizeof(check_file))
    698 			err(2, "CHECK_PATH too long");
    699 
    700 		if (strlcat(check_file, "/", sizeof(check_file))
    701 		    >= sizeof(check_file))
    702 			err(2, "Could not append / to check file path");
    703 	} else {
    704 		check_file[0] = '\0';
    705 	}
    706 
    707 	if (strlcat(check_file, filename, sizeof(check_file))
    708 	    >= sizeof(check_file))
    709 		err(2, "Path to check file path overflowed");
    710 
    711 	if ((check_fd = open(check_file, O_RDONLY, 0)) < 0)
    712 		err(2, "failed to open file %s line %zu of file %s",
    713 		    check_file, line, cur_file);
    714 
    715 	fds[0].fd = check_fd;
    716 	fds[0].events = POLLIN;
    717 	fds[0].revents = 0;
    718 	fds[1].fd = master;
    719 	fds[1].events = POLLIN;
    720 	fds[1].revents = 0;
    721 
    722 	nfd = 2;
    723 	/*
    724 	 * if we have saved output then only check for data in the
    725 	 * reference file since the slave data may already be drained.
    726 	 */
    727 	if (saved_output.count > 0)
    728 		nfd = 1;
    729 
    730 	while (poll(&fds[0], nfd, 500) == nfd) {
    731 		if ((result = read(check_fd, &ref, 1)) < 1) {
    732 			if (result != 0) {
    733 				err(2, "Bad read on file %s", check_file);
    734 			} else {
    735 				break;
    736 			}
    737 		}
    738 
    739 		if (saved_output.count > 0) {
    740 			data = saved_output.data[saved_output.readp];
    741 			saved_output.count--;
    742 			saved_output.readp++;
    743 			/* run out of saved data, switch to file */
    744 			if (saved_output.count == 0)
    745 				nfd = 2;
    746 		} else {
    747 			if (read(master, &data, 1) < 1)
    748 				err(2, "Bad read on slave pty");
    749 		}
    750 
    751 		if (verbose) {
    752 			fprintf(stderr, "Comparing reference byte 0x%x (%c)"
    753 				" against slave byte 0x%x (%c)\n", ref,
    754 				(ref >= ' ')? ref : '-',
    755 				data, (data >= ' ')? data : '-');
    756 		}
    757 
    758 		if (ref != data) {
    759 			warnx("%s, %zu: refresh data from slave does "
    760 			    "not match expected from file %s",
    761 			    cur_file, line, check_file);
    762 
    763 			if (!verbose)
    764 				exit(2);
    765 		}
    766 
    767 		fds[0].revents = 0;
    768 		fds[1].revents = 0;
    769 	}
    770 
    771 
    772 	if (saved_output.count > 0)
    773 		excess(cur_file, line, __func__, " from slave",
    774 		    &saved_output.data[saved_output.readp], saved_output.count);
    775 
    776 	/* discard any excess saved output if required */
    777 	if (discard) {
    778 		saved_output.count = 0;
    779 		saved_output.readp = 0;
    780 	}
    781 
    782 	fds[0].revents = 0;
    783 	fds[1].revents = 0;
    784 	if ((result = poll(&fds[0], 2, 0)) != 0) {
    785 		if (result == -1)
    786 			err(2, "poll of file descriptors failed");
    787 
    788 		if ((fds[1].revents & POLLIN) == POLLIN) {
    789 			save_slave_output(true);
    790 		} else {
    791 			/*
    792 			 * handle excess in file if it exists.  Poll
    793 			 * says there is data until EOF is read.
    794 			 * Check next read is EOF, if it is not then
    795 			 * the file really has more data than the
    796 			 * slave produced so flag this as a warning.
    797 			 */
    798 			result = read(check_fd, drain, sizeof(drain));
    799 			if (result == -1)
    800 				err(1, "read of data file failed");
    801 
    802 			if (result > 0) {
    803 				excess(check_file, 0, __func__, "", drain,
    804 				    result);
    805 				if (!verbose)
    806 					exit(2);
    807 			}
    808 		}
    809 	}
    810 
    811 	close(check_fd);
    812 }
    813 
    814 /*
    815  * Pass a function call and arguments to the slave and wait for the
    816  * results.  The variable nresults determines how many returns we expect
    817  * back from the slave.  These results will be validated against the
    818  * expected returns or assigned to variables.
    819  */
    820 static void
    821 do_function_call(size_t nresults)
    822 {
    823 #define MAX_RESULTS 4
    824 	char *p;
    825 	int do_input;
    826 	size_t i;
    827 	struct pollfd fds[3];
    828 	returns_t response[MAX_RESULTS], returns_count;
    829 
    830 	assert(nresults <= MAX_RESULTS);
    831 
    832 	do_input = check_function_table(command.function, input_functions,
    833 	    ninput_functions);
    834 
    835 	write_func_and_args();
    836 
    837 	/*
    838 	 * We should get the number of returns back here, grab it before
    839 	 * doing input otherwise it will confuse the input poll
    840 	 */
    841 	read_cmd_pipe(&returns_count);
    842 	if (returns_count.return_type != ret_count)
    843 		err(2, "expected return type of ret_count but received %s",
    844 		    returns_enum_names[returns_count.return_type]);
    845 
    846 	if (verbose)
    847 		fprintf(stderr, "Expect %zu results from slave, slave "
    848 			"reported %zu\n", nresults, returns_count.return_len);
    849 
    850 	if ((no_input == false) && (do_input == 1)) {
    851 		if (verbose)
    852 			fprintf(stderr, "doing input with inputstr >%s<\n",
    853 				input_str);
    854 
    855 		if (input_str == NULL)
    856 			errx(2, "%s, %zu: Call to input function "
    857 			    "but no input defined", cur_file, line);
    858 
    859 		fds[0].fd = slvpipe[READ_PIPE];
    860 		fds[0].events = POLLIN;
    861  		p = input_str;
    862 		save_slave_output(false);
    863 		while(*p != '\0') {
    864 			if (verbose) {
    865 				fprintf(stderr, "Writing char >%c< to slave\n",
    866 					*p);
    867 				fflush(stderr);
    868 			}
    869 
    870 			nanosleep(&delay_spec, NULL);
    871 
    872 			write(master, p, 1);
    873 			save_slave_output(false);
    874 
    875 			p++;
    876 			fds[0].revents = 0;
    877 
    878 			/* check for slave function returning unexpectedly */
    879 			if ((poll(&fds[0], 1, 10) > 0) && (*p != '\0')) {
    880 				warnx("%s, %zu: Slave function "
    881 				    "returned before end of input string",
    882 				    cur_file, line);
    883 				break;
    884 			}
    885 		}
    886 
    887 		if (verbose) {
    888 			fprintf(stderr, "Input done.\n");
    889 		}
    890 
    891 		/* done with the input string, free the resources */
    892 		free(input_str);
    893 		input_str = NULL;
    894 	}
    895 
    896 	if (verbose) {
    897 		fds[0].fd = slvpipe[READ_PIPE];
    898 		fds[0].events = POLLIN;
    899 		fds[0].revents = 0;
    900 
    901 		fds[1].fd = slvpipe[WRITE_PIPE];
    902 		fds[1].events = POLLOUT;
    903 		fds[1].revents = 0;
    904 
    905 		fds[2].fd = master;
    906 		fds[2].events = POLLIN | POLLOUT;
    907 		fds[2].revents = 0;
    908 
    909 		i = poll(&fds[0], 3, 1000);
    910 		fprintf(stderr, "Poll returned %zu\n", i);
    911 		for (i = 0; i < 3; i++) {
    912 			fprintf(stderr, "revents for fd[%zu] = 0x%x\n",
    913 				i, fds[i].revents);
    914 		}
    915 	}
    916 
    917 	/* drain any trailing output */
    918 	save_slave_output(false);
    919 
    920 	for (i = 0; i < returns_count.return_len; i++) {
    921 		read_cmd_pipe(&response[i]);
    922 	}
    923 
    924 	/*
    925 	 * Check for a slave error in the first return slot, if the
    926 	 * slave errored then we may not have the number of returns we
    927 	 * expect but in this case we should report the slave error
    928 	 * instead of a return count mismatch.
    929 	 */
    930 	if ((returns_count.return_len > 0) &&
    931 	    (response[0].return_type == ret_slave_error))
    932 		err(2, "Slave returned error: %s",
    933 		    (const char *)response[0].return_value);
    934 
    935 	if (returns_count.return_len != nresults)
    936 		err(2, "Incorrect number of returns from slave, expected %zu "
    937 		    "but received %zu", nresults, returns_count.return_len);
    938 
    939 	if (verbose) {
    940 		for (i = 0; i < nresults; i++) {
    941 			if ((response[i].return_type != ret_byte) &&
    942 			    (response[i].return_type != ret_err) &&
    943 			    (response[i].return_type != ret_ok))
    944 				fprintf(stderr,
    945 					"received response >%s< "
    946 					"expected",
    947 					(const char *)response[i].return_value);
    948 			else
    949 				fprintf(stderr, "received");
    950 
    951 			fprintf(stderr, " return_type %s\n",
    952 			    returns_enum_names[command.returns[i].return_type]);
    953 		}
    954 	}
    955 
    956 	for (i = 0; i < nresults; i++) {
    957 		if (command.returns[i].return_type != ret_var) {
    958 			validate(i, &response[i]);
    959 		} else {
    960 			vars[command.returns[i].return_index].len =
    961 				response[i].return_len;
    962 			vars[command.returns[i].return_index].value =
    963 				response[i].return_value;
    964 			vars[command.returns[i].return_index].type =
    965 				response[i].return_type;
    966 		}
    967 	}
    968 #if 0
    969 	if (saved_output.count > 0)
    970 		excess(cur_file, line, __func__, " from slave",
    971 		    &saved_output.data[saved_output.readp], saved_output.count);
    972 #endif
    973 
    974 	init_parse_variables(0);
    975 }
    976 
    977 /*
    978  * Write the function and command arguments to the command pipe.
    979  */
    980 static void
    981 write_func_and_args(void)
    982 {
    983 	int i;
    984 
    985 	if (verbose)
    986 		fprintf(stderr, "calling function >%s<\n", command.function);
    987 
    988 	write_cmd_pipe(command.function);
    989 	for (i = 0; i < command.nargs; i++) {
    990 		if (command.args[i].arg_type == arg_var)
    991 			write_cmd_pipe_args(command.args[i].arg_type,
    992 					    &vars[command.args[i].var_index]);
    993 		else
    994 			write_cmd_pipe_args(command.args[i].arg_type,
    995 					    &command.args[i]);
    996 	}
    997 
    998 	write_cmd_pipe(NULL); /* signal end of arguments */
    999 }
   1000 
   1001 /*
   1002  * Initialise the command structure - if initial is non-zero then just set
   1003  * everything to sane values otherwise free any memory that was allocated
   1004  * when building the structure.
   1005  */
   1006 void
   1007 init_parse_variables(int initial)
   1008 {
   1009 	int i, result;
   1010 	struct pollfd slave_pty;
   1011 
   1012 	if (initial == 0) {
   1013 		free(command.function);
   1014 		for (i = 0; i < command.nrets; i++) {
   1015 			if (command.returns[i].return_type == ret_number)
   1016 				free(command.returns[i].return_value);
   1017 		}
   1018 		free(command.returns);
   1019 
   1020 		for (i = 0; i < command.nargs; i++) {
   1021 			if (command.args[i].arg_type != arg_var)
   1022 				free(command.args[i].arg_string);
   1023 		}
   1024 		free(command.args);
   1025 	} else {
   1026 		line = 0;
   1027 		input_delay = 0;
   1028 		vars = NULL;
   1029 		nvars = 0;
   1030 		input_str = NULL;
   1031 		saved_output.allocated = 0;
   1032 		saved_output.count = 0;
   1033 		saved_output.readp = 0;
   1034 		saved_output.data = NULL;
   1035 	}
   1036 
   1037 	no_input = false;
   1038 	command.function = NULL;
   1039 	command.nargs = 0;
   1040 	command.args = NULL;
   1041 	command.nrets = 0;
   1042 	command.returns = NULL;
   1043 
   1044 	/*
   1045 	 * Check the slave pty for stray output from the slave, at this
   1046 	 * point we should not see any data as it should have been
   1047 	 * consumed by the test functions.  If we see data then we have
   1048 	 * either a bug or are not handling an output generating function
   1049 	 * correctly.
   1050 	 */
   1051 	slave_pty.fd = master;
   1052 	slave_pty.events = POLLIN;
   1053 	slave_pty.revents = 0;
   1054 	result = poll(&slave_pty, 1, 0);
   1055 
   1056 	if (result < 0)
   1057 		err(2, "Poll of slave pty failed");
   1058 	else if (result > 0)
   1059 		warnx("%s, %zu: Unexpected data from slave", cur_file, line);
   1060 }
   1061 
   1062 /*
   1063  * Validate the response against the expected return.  The variable
   1064  * i is the i into the rets array in command.
   1065  */
   1066 static void
   1067 validate(int i, void *data)
   1068 {
   1069 	char *response;
   1070 	returns_t *byte_response;
   1071 
   1072 	byte_response = data;
   1073 	if ((command.returns[i].return_type != ret_byte) &&
   1074 	    (command.returns[i].return_type != ret_err) &&
   1075 	    (command.returns[i].return_type != ret_ok))
   1076 		response = byte_response->return_value;
   1077 
   1078 	switch (command.returns[i].return_type) {
   1079 	case ret_err:
   1080 		validate_type(ret_err, byte_response, 0);
   1081 		break;
   1082 
   1083 	case ret_ok:
   1084 		validate_type(ret_ok, byte_response, 0);
   1085 		break;
   1086 
   1087 	case ret_null:
   1088 		validate_return("NULL", response, 0);
   1089 		break;
   1090 
   1091 	case ret_nonnull:
   1092 		validate_return("NULL", response, 1);
   1093 		break;
   1094 
   1095 	case ret_string:
   1096 	case ret_number:
   1097 		validate_return(command.returns[i].return_value,
   1098 				response, 0);
   1099 		break;
   1100 
   1101 	case ret_ref:
   1102 		validate_reference(i, response);
   1103 		break;
   1104 
   1105 	case ret_byte:
   1106 		validate_byte(&command.returns[i], byte_response, 0);
   1107 		break;
   1108 
   1109 	default:
   1110 		err(1, "Malformed statement at line %zu of file %s",
   1111 		    line, cur_file);
   1112 		break;
   1113 	}
   1114 }
   1115 
   1116 /*
   1117  * Validate the return against the contents of a variable.
   1118  */
   1119 static void
   1120 validate_reference(int i, void *data)
   1121 {
   1122 	char *response;
   1123 	returns_t *byte_response;
   1124 	var_t *varp;
   1125 
   1126 	varp = &vars[command.returns[i].return_index];
   1127 
   1128 	byte_response = data;
   1129 	if (command.returns[i].return_type != ret_byte)
   1130 		response = data;
   1131 
   1132 	if (verbose)
   1133 		fprintf(stderr,
   1134 			"validate_reference: return type of %s, value %s \n",
   1135 			returns_enum_names[varp->type],
   1136 			(const char *)varp->value);
   1137 
   1138 	switch (varp->type) {
   1139 	case ret_string:
   1140 	case ret_number:
   1141 		validate_return(varp->value, response, 0);
   1142 		break;
   1143 
   1144 	case ret_byte:
   1145 		validate_byte(varp->value, byte_response, 0);
   1146 		break;
   1147 
   1148 	default:
   1149 		err(1,
   1150 		    "Invalid return type for reference at line %zu of file %s",
   1151 		    line, cur_file);
   1152 		break;
   1153 	}
   1154 }
   1155 
   1156 /*
   1157  * Validate the return type against the expected type, throw an error
   1158  * if they don't match.
   1159  */
   1160 static void
   1161 validate_type(returns_enum_t expected, returns_t *value, int check)
   1162 {
   1163 	if (((check == 0) && (expected != value->return_type)) ||
   1164 	    ((check == 1) && (expected == value->return_type)))
   1165 		err(1, "Validate expected type %s %s %s line %zu of file %s",
   1166 		    returns_enum_names[expected],
   1167 		    (check == 0)? "matching" : "not matching",
   1168 		    returns_enum_names[value->return_type], line, cur_file);
   1169 
   1170 	if (verbose)
   1171 		fprintf(stderr, "Validate expected type %s %s %s line %zu"
   1172 			" of file %s\n",
   1173 			returns_enum_names[expected],
   1174 			(check == 0)? "matching" : "not matching",
   1175 			returns_enum_names[value->return_type], line, cur_file);
   1176 }
   1177 
   1178 /*
   1179  * Validate the return value against the expected value, throw an error
   1180  * if they don't match.
   1181  */
   1182 static void
   1183 validate_return(const char *expected, const char *value, int check)
   1184 {
   1185 	if (((check == 0) && strcmp(expected, value) != 0) ||
   1186 	    ((check == 1) && strcmp(expected, value) == 0))
   1187 		err(1, "Validate expected %s %s %s line %zu of file %s",
   1188 		    expected,
   1189 		    (check == 0)? "matching" : "not matching", value,
   1190 		    line, cur_file);
   1191 	if (verbose)
   1192 		fprintf(stderr, "Validated expected value %s %s %s "
   1193 			"at line %zu of file %s\n", expected,
   1194 			(check == 0)? "matches" : "does not match",
   1195 			value, line, cur_file);
   1196 }
   1197 
   1198 /*
   1199  * Validate the return value against the expected value, throw an error
   1200  * if they don't match expectations.
   1201  */
   1202 static void
   1203 validate_byte(returns_t *expected, returns_t *value, int check)
   1204 {
   1205 	/*
   1206 	 * No chance of a match if lengths differ...
   1207 	 */
   1208 	if ((check == 0) && (expected->return_len != value->return_len))
   1209 	    err(1, "Byte validation failed, length mismatch");
   1210 
   1211 	/*
   1212 	 * If check is 0 then we want to throw an error IFF the byte streams
   1213 	 * do not match, if check is 1 then throw an error if the byte
   1214 	 * streams match.
   1215 	 */
   1216 	if (((check == 0) && memcmp(expected->return_value, value->return_value,
   1217 				    value->return_len) != 0) ||
   1218 	    ((check == 1) && (expected->return_len == value->return_len) &&
   1219 	     memcmp(expected->return_value, value->return_value,
   1220 		    value->return_len) == 0))
   1221 		err(1, "Validate expected %s byte stream at line %zu"
   1222 		    "of file %s",
   1223 		    (check == 0)? "matching" : "not matching", line, cur_file);
   1224 	if (verbose)
   1225 		fprintf(stderr, "Validated expected %s byte stream "
   1226 			"at line %zu of file %s\n",
   1227 			(check == 0)? "matching" : "not matching",
   1228 			line, cur_file);
   1229 }
   1230 
   1231 /*
   1232  * Validate the variable at i against the expected value, throw an
   1233  * error if they don't match, if check is non-zero then the match is
   1234  * negated.
   1235  */
   1236 static void
   1237 validate_variable(int ret, returns_enum_t type, const void *value, int i,
   1238     int check)
   1239 {
   1240 	returns_t *retval;
   1241 	var_t *varptr;
   1242 
   1243 	retval = &command.returns[ret];
   1244 	varptr = &vars[command.returns[ret].return_index];
   1245 
   1246 	if (varptr->value == NULL)
   1247 		err(1, "Variable %s has no value assigned to it", varptr->name);
   1248 
   1249 
   1250 	if (varptr->type != type)
   1251 		err(1, "Variable %s is not the expected type", varptr->name);
   1252 
   1253 	if (type != ret_byte) {
   1254 		if ((((check == 0) && strcmp(value, varptr->value) != 0))
   1255 		    || ((check == 1) && strcmp(value, varptr->value) == 0))
   1256 			err(1, "Variable %s contains %s instead of %s"
   1257 			    " value %s at line %zu of file %s",
   1258 			    varptr->name, (const char *)varptr->value,
   1259 			    (check == 0)? "expected" : "not matching",
   1260 			    (const char *)value,
   1261 			    line, cur_file);
   1262 		if (verbose)
   1263 			fprintf(stderr, "Variable %s contains %s value "
   1264 				"%s at line %zu of file %s\n",
   1265 				varptr->name,
   1266 				(check == 0)? "expected" : "not matching",
   1267 				(const char *)varptr->value, line, cur_file);
   1268 	} else {
   1269 		if ((check == 0) && (retval->return_len != varptr->len))
   1270 			err(1, "Byte validation failed, length mismatch");
   1271 
   1272 		/*
   1273 		 * If check is 0 then we want to throw an error IFF
   1274 		 * the byte streams do not match, if check is 1 then
   1275 		 * throw an error if the byte streams match.
   1276 		 */
   1277 		if (((check == 0) && memcmp(retval->return_value, varptr->value,
   1278 					    varptr->len) != 0) ||
   1279 		    ((check == 1) && (retval->return_len == varptr->len) &&
   1280 		     memcmp(retval->return_value, varptr->value,
   1281 			    varptr->len) == 0))
   1282 			err(1, "Validate expected %s byte stream at line %zu"
   1283 			    " of file %s",
   1284 			    (check == 0)? "matching" : "not matching",
   1285 			    line, cur_file);
   1286 		if (verbose)
   1287 			fprintf(stderr, "Validated expected %s byte stream "
   1288 				"at line %zu of file %s\n",
   1289 				(check == 0)? "matching" : "not matching",
   1290 				line, cur_file);
   1291 	}
   1292 }
   1293 
   1294 /*
   1295  * Write a string to the command pipe - we feed the number of bytes coming
   1296  * down first to allow storage allocation and then follow up with the data.
   1297  * If cmd is NULL then feed a -1 down the pipe to say the end of the args.
   1298  */
   1299 static void
   1300 write_cmd_pipe(char *cmd)
   1301 {
   1302 	args_t arg;
   1303 	size_t len;
   1304 
   1305 	if (cmd == NULL)
   1306 		len = 0;
   1307 	else
   1308 		len = strlen(cmd);
   1309 
   1310 	arg.arg_type = arg_static;
   1311 	arg.arg_len = len;
   1312 	arg.arg_string = cmd;
   1313 	write_cmd_pipe_args(arg.arg_type, &arg);
   1314 
   1315 }
   1316 
   1317 static void
   1318 write_cmd_pipe_args(args_state_t type, void *data)
   1319 {
   1320 	var_t *var_data;
   1321 	args_t *arg_data;
   1322 	int len, send_type;
   1323 	void *cmd;
   1324 
   1325 	arg_data = data;
   1326 	switch (type) {
   1327 	case arg_var:
   1328 		var_data = data;
   1329 		len = var_data->len;
   1330 		cmd = var_data->value;
   1331 		if (type == arg_byte)
   1332 			send_type = ret_byte;
   1333 		else
   1334 			send_type = ret_string;
   1335 		break;
   1336 
   1337 	case arg_null:
   1338 		send_type = ret_null;
   1339 		len = 0;
   1340 		break;
   1341 
   1342 	default:
   1343 		if ((arg_data->arg_len == 0) && (arg_data->arg_string == NULL))
   1344 			len = -1;
   1345 		else
   1346 			len = arg_data->arg_len;
   1347 		cmd = arg_data->arg_string;
   1348 		if (type == arg_byte)
   1349 			send_type = ret_byte;
   1350 		else
   1351 			send_type = ret_string;
   1352 	}
   1353 
   1354 	if (verbose)
   1355 		fprintf(stderr, "Writing type %s to command pipe\n",
   1356 			returns_enum_names[send_type]);
   1357 
   1358 	if (write(cmdpipe[WRITE_PIPE], &send_type, sizeof(int)) < 0)
   1359 		err(1, "command pipe write for type failed");
   1360 
   1361 	if (verbose)
   1362 		fprintf(stderr, "Writing length %d to command pipe\n", len);
   1363 
   1364 	if (write(cmdpipe[WRITE_PIPE], &len, sizeof(int)) < 0)
   1365 		err(1, "command pipe write for length failed");
   1366 
   1367 	if (len > 0) {
   1368 		if (verbose)
   1369 			fprintf(stderr, "Writing data >%s< to command pipe\n",
   1370 				(const char *)cmd);
   1371 		if (write(cmdpipe[WRITE_PIPE], cmd, len) < 0)
   1372 			err(1, "command pipe write of data failed");
   1373 	}
   1374 }
   1375 
   1376 /*
   1377  * Read a response from the command pipe, first we will receive the
   1378  * length of the response then the actual data.
   1379  */
   1380 static void
   1381 read_cmd_pipe(returns_t *response)
   1382 {
   1383 	int len, type;
   1384 	struct pollfd rfd[2];
   1385 	char *str;
   1386 
   1387 	/*
   1388 	 * Check if there is data to read - just in case slave has died, we
   1389 	 * don't want to block on the read and just hang.  We also check
   1390 	 * output from the slave because the slave may be blocked waiting
   1391 	 * for a flush on its stdout.
   1392 	 */
   1393 	rfd[0].fd = slvpipe[READ_PIPE];
   1394 	rfd[0].events = POLLIN;
   1395 	rfd[1].fd = master;
   1396 	rfd[1].events = POLLIN;
   1397 
   1398 	do {
   1399 		rfd[0].revents = 0;
   1400 		rfd[1].revents = 0;
   1401 
   1402 		if (poll(rfd, 2, 4000) == 0)
   1403 			errx(2, "%s, %zu: Command pipe read timeout",
   1404 			    cur_file, line);
   1405 
   1406 		if ((rfd[1].revents & POLLIN) == POLLIN) {
   1407 			if (verbose)
   1408 				fprintf(stderr,
   1409 					"draining output from slave\n");
   1410 			save_slave_output(false);
   1411 		}
   1412 	}
   1413 	while((rfd[1].revents & POLLIN) == POLLIN);
   1414 
   1415 	if (read(slvpipe[READ_PIPE], &type, sizeof(int)) < 0)
   1416 		err(1, "command pipe read for type failed");
   1417 	response->return_type = type;
   1418 
   1419 	if ((type != ret_ok) && (type != ret_err) && (type != ret_count)) {
   1420 		if (read(slvpipe[READ_PIPE], &len, sizeof(int)) < 0)
   1421 			err(1, "command pipe read for length failed");
   1422 		response->return_len = len;
   1423 
   1424 		if (verbose)
   1425 			fprintf(stderr,
   1426 				"Reading %d bytes from command pipe\n", len);
   1427 
   1428 		if ((response->return_value = malloc(len + 1)) == NULL)
   1429 			err(1, "Failed to alloc memory for cmd pipe read");
   1430 
   1431 		if (read(slvpipe[READ_PIPE], response->return_value, len) < 0)
   1432 			err(1, "command pipe read of data failed");
   1433 
   1434 		if (response->return_type != ret_byte) {
   1435 			str = response->return_value;
   1436 			str[len] = '\0';
   1437 
   1438 			if (verbose)
   1439 				fprintf(stderr, "Read data >%s< from pipe\n",
   1440 					(const char *)response->return_value);
   1441 		}
   1442 	} else {
   1443 		response->return_value = NULL;
   1444 		if (type == ret_count) {
   1445 			if (read(slvpipe[READ_PIPE], &len, sizeof(int)) < 0)
   1446 				err(1, "command pipe read for number of "
   1447 				       "returns failed");
   1448 			response->return_len = len;
   1449 		}
   1450 
   1451 		if (verbose)
   1452 			fprintf(stderr, "Read type %s from pipe\n",
   1453 				returns_enum_names[type]);
   1454 	}
   1455 }
   1456 
   1457 /*
   1458  * Check for writes from the slave on the pty, save the output into a
   1459  * buffer for later checking if discard is false.
   1460  */
   1461 #define MAX_DRAIN 256
   1462 
   1463 static void
   1464 save_slave_output(bool discard)
   1465 {
   1466 	struct pollfd fd;
   1467 	char *new_data, drain[MAX_DRAIN];
   1468 	size_t to_allocate;
   1469 	ssize_t result;
   1470 	size_t i;
   1471 
   1472 	fd.fd = master;
   1473 	fd.events = POLLIN;
   1474 	fd.revents = 0;
   1475 
   1476 	result = 0;
   1477 	while (1) {
   1478 		if (result == -1)
   1479 			err(2, "poll of slave pty failed");
   1480 		result = MAX_DRAIN;
   1481 		if ((result = read(master, &drain, result)) < 0) {
   1482 			if (errno == EAGAIN)
   1483 				break;
   1484 			else
   1485 				err(2, "draining slave pty failed");
   1486 		}
   1487 
   1488 		fd.revents = 0;
   1489 		if (!discard) {
   1490 			if ((size_t)result >
   1491 			    (saved_output.allocated - saved_output.count)) {
   1492 				to_allocate = 1024 * ((result / 1024) + 1);
   1493 
   1494 				if ((new_data = realloc(saved_output.data,
   1495 					saved_output.allocated + to_allocate))
   1496 				    == NULL)
   1497 					err(2, "Realloc of saved_output failed");
   1498 				saved_output.data = new_data;
   1499 				saved_output.allocated += to_allocate;
   1500 			}
   1501 
   1502 			if (verbose) {
   1503 				fprintf(stderr, "count = %zu, "
   1504 				    "allocated = %zu\n", saved_output.count,
   1505 				    saved_output.allocated);
   1506 				for (i = 0; i < (size_t)result; i++) {
   1507 					fprintf(stderr, "Saving slave output "
   1508 					    "0x%x (%c)\n", drain[i],
   1509 					    (drain[i] >= ' ')? drain[i] : '-');
   1510 				}
   1511 			}
   1512 
   1513 			memcpy(&saved_output.data[saved_output.count], drain,
   1514 			       result);
   1515 			saved_output.count += result;
   1516 
   1517 			if (verbose) {
   1518 				fprintf(stderr, "count = %zu, "
   1519 				    "allocated = %zu\n", saved_output.count,
   1520 				    saved_output.allocated);
   1521 			}
   1522 		} else {
   1523 			if (verbose) {
   1524 				for (i=0; i < (size_t)result; i++) {
   1525 					fprintf(stderr, "Discarding slave "
   1526 					    "output 0x%x (%c)\n",
   1527 					    drain[i],
   1528 					    (drain[i] >= ' ')? drain[i] : '-');
   1529 				}
   1530 			}
   1531 		}
   1532 	}
   1533 }
   1534 
   1535 static void
   1536 yyerror(const char *msg)
   1537 {
   1538 	warnx("%s in line %zu of file %s", msg, line, cur_file);
   1539 }
   1540