path: root/usr.bin/lex/misc.c

/*	$OpenBSD: misc.c,v 1.21 2024/11/09 18:03:44 op Exp $	*/

/* misc - miscellaneous flex routines */

/*  Copyright (c) 1990 The Regents of the University of California. */
/*  All rights reserved. */

/*  This code is derived from software contributed to Berkeley by */
/*  Vern Paxson. */

/*  The United States Government has rights in this work pursuant */
/*  to contract no. DE-AC03-76SF00098 between the United States */
/*  Department of Energy and the University of California. */

/*  This file is part of flex. */

/*  Redistribution and use in source and binary forms, with or without */
/*  modification, are permitted provided that the following conditions */
/*  are met: */

/*  1. Redistributions of source code must retain the above copyright */
/*     notice, this list of conditions and the following disclaimer. */
/*  2. Redistributions in binary form must reproduce the above copyright */
/*     notice, this list of conditions and the following disclaimer in the */
/*     documentation and/or other materials provided with the distribution. */

/*  Neither the name of the University nor the names of its contributors */
/*  may be used to endorse or promote products derived from this software */
/*  without specific prior written permission. */

/*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR */
/*  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED */
/*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR */
/*  PURPOSE. */

#include "flexdef.h"
#include "tables.h"

#define CMD_IF_TABLES_SER    "%if-tables-serialization"
#define CMD_TABLES_YYDMAP    "%tables-yydmap"
#define CMD_DEFINE_YYTABLES  "%define-yytables"
#define CMD_IF_CPP_ONLY      "%if-c++-only"
#define CMD_IF_C_ONLY        "%if-c-only"
#define CMD_IF_C_OR_CPP      "%if-c-or-c++"
#define CMD_NOT_FOR_HEADER   "%not-for-header"
#define CMD_OK_FOR_HEADER    "%ok-for-header"
#define CMD_PUSH             "%push"
#define CMD_POP              "%pop"
#define CMD_IF_REENTRANT     "%if-reentrant"
#define CMD_IF_NOT_REENTRANT "%if-not-reentrant"
#define CMD_IF_BISON_BRIDGE  "%if-bison-bridge"
#define CMD_IF_NOT_BISON_BRIDGE  "%if-not-bison-bridge"
#define CMD_ENDIF            "%endif"

/* we allow the skeleton to push and pop. */
struct sko_state {
	bool dc;		/**< do_copy */
};
static struct sko_state *sko_stack = 0;
static int sko_len = 0, sko_sz = 0;
static void 
sko_push(bool dc)
{
	if (!sko_stack) {
		sko_sz = 1;
		sko_stack = malloc(sizeof(struct sko_state) * sko_sz);
		if (!sko_stack)
			flexfatal(_("allocation of sko_stack failed"));
		sko_len = 0;
	}
	if (sko_len >= sko_sz) {
		sko_sz *= 2;
		sko_stack = realloc(sko_stack, sizeof(struct sko_state) * sko_sz);
	}
	/* initialize to zero and push */
	sko_stack[sko_len].dc = dc;
	sko_len++;
}
static void 
sko_peek(bool * dc)
{
	if (sko_len <= 0)
		flex_die("peek attempt when sko stack is empty");
	if (dc)
		*dc = sko_stack[sko_len - 1].dc;
}
static void 
sko_pop(bool * dc)
{
	sko_peek(dc);
	sko_len--;
	if (sko_len < 0)
		flex_die("popped too many times in skeleton.");
}

/* Append "#define defname value\n" to the running buffer. */
void 
action_define(const char *defname, int value)
{
	char buf[MAXLINE];
	char *cpy;

	if ((int) strlen(defname) > MAXLINE / 2) {
		format_pinpoint_message(_
		    ("name \"%s\" ridiculously long"),
		    defname);
		return;
	}
	snprintf(buf, sizeof(buf), "#define %s %d\n", defname, value);
	add_action(buf);

	/* track #defines so we can undef them when we're done. */
	cpy = copy_string(defname);
	buf_append(&defs_buf, &cpy, 1);
}


/* Append "new_text" to the running buffer. */
void 
add_action(const char *new_text)
{
	int len = strlen(new_text);

	while (len + action_index >= action_size - 10 /* slop */ ) {
		int new_size = action_size * 2;

		if (new_size <= 0)
			/*
			 * Increase just a little, to try to avoid overflow
			 * on 16-bit machines.
			 */
			action_size += action_size / 8;
		else
			action_size = new_size;

		action_array =
		    reallocate_character_array(action_array,
		    action_size);
	}

	strlcpy(&action_array[action_index], new_text,
	    action_size - action_index);

	action_index += len;
}


/* allocate_array - allocate memory for an integer array of the given size */

void *
allocate_array(int size, size_t element_size)
{
	void *mem;
	size_t num_bytes = element_size * size;

	mem = malloc(num_bytes);
	if (!mem)
		flexfatal(_
		    ("memory allocation failed in allocate_array()"));

	return mem;
}


/* all_lower - true if a string is all lower-case */

int 
all_lower(char *str)
{
	while (*str) {
		if (!isascii((u_char) * str) || !islower((u_char) * str))
			return 0;
		++str;
	}

	return 1;
}


/* all_upper - true if a string is all upper-case */

int 
all_upper(char *str)
{
	while (*str) {
		if (!isascii((u_char) * str) || !isupper((u_char) * str))
			return 0;
		++str;
	}

	return 1;
}


/* intcmp - compares two integers for use by qsort. */

int 
intcmp(const void *a, const void *b)
{
	return *(const int *) a - *(const int *) b;
}


/* check_char - checks a character to make sure it's within the range
 *		we're expecting.  If not, generates fatal error message
 *		and exits.
 */

void 
check_char(int c)
{
	if (c >= CSIZE)
		lerrsf(_("bad character '%s' detected in check_char()"),
		    readable_form(c));

	if (c >= csize)
		lerrsf(_
		    ("scanner requires -8 flag to use the character %s"),
		    readable_form(c));
}



/* clower - replace upper-case letter to lower-case */

u_char 
clower(int c)
{
	return (u_char) ((isascii(c) && isupper(c)) ? tolower(c) : c);
}


/* copy_string - returns a dynamically allocated copy of a string */

char *
copy_string(const char *str)
{
	const char *c1;
	char *c2;
	char *copy;
	unsigned int size;

	/* find length */
	for (c1 = str; *c1; ++c1);

	size = (c1 - str + 1) * sizeof(char);

	copy = (char *) malloc(size);

	if (copy == NULL)
		flexfatal(_("dynamic memory failure in copy_string()"));

	for (c2 = copy; (*c2++ = *str++) != 0;);

	return copy;
}


/* copy_unsigned_string -
 *    returns a dynamically allocated copy of a (potentially) unsigned string
 */

u_char *
copy_unsigned_string(unsigned char *str)
{
	u_char *c;
	u_char *copy;

	/* find length */
	for (c = str; *c; ++c);

	copy = allocate_Character_array(c - str + 1);

	for (c = copy; (*c++ = *str++) != 0;);

	return copy;
}


/* cclcmp - compares two characters for use by qsort with '\0' sorting last. */

int 
cclcmp(const void *a, const void *b)
{
	if (!*(const u_char *) a)
		return 1;
	else if (!*(const u_char *) b)
		return -1;
	else
		return *(const u_char *) a - *(const u_char *) b;
}


/* dataend - finish up a block of data declarations */

void 
dataend(void)
{
	/* short circuit any output */
	if (gentables) {

		if (datapos > 0)
			dataflush();

		/* add terminator for initialization; { for vi */
		outn("    } ;\n");
	}
	dataline = 0;
	datapos = 0;
}


/* dataflush - flush generated data statements */

void 
dataflush(void)
{
	/* short circuit any output */
	if (!gentables)
		return;

	outc('\n');

	if (++dataline >= NUMDATALINES) {
		/*
		 * Put out a blank line so that the table is grouped into
		 * large blocks that enable the user to find elements easily.
		 */
		outc('\n');
		dataline = 0;
	}
	/* Reset the number of characters written on the current line. */
	datapos = 0;
}


/* flexerror - report an error message and terminate */

void 
flexerror(const char *msg)
{
	fprintf(stderr, "%s: %s\n", program_name, msg);
	flexend(1);
}


/* flexfatal - report a fatal error message and terminate */

void 
flexfatal(const char *msg)
{
	fprintf(stderr, _("%s: fatal internal error, %s\n"),
	    program_name, msg);
	FLEX_EXIT(1);
}


/* htoi - convert a hexadecimal digit string to an integer value */

int 
htoi(unsigned char str[])
{
	unsigned int result;

	(void) sscanf((char *) str, "%x", &result);

	return result;
}


/* lerrif - report an error message formatted with one integer argument */

void 
lerrif(const char *msg, int arg)
{
	char errmsg[MAXLINE];

	snprintf(errmsg, sizeof(errmsg), msg, arg);
	flexerror(errmsg);
}


/* lerrsf - report an error message formatted with one string argument */

void 
lerrsf(const char *msg, const char arg[])
{
	char errmsg[MAXLINE];

	snprintf(errmsg, sizeof(errmsg) - 1, msg, arg);
	errmsg[sizeof(errmsg) - 1] = 0;	/* ensure NULL termination */
	flexerror(errmsg);
}


/* lerrsf_fatal - as lerrsf, but call flexfatal */

void 
lerrsf_fatal(const char *msg, const char arg[])
{
	char errmsg[MAXLINE];

	snprintf(errmsg, sizeof(errmsg) - 1, msg, arg);
	errmsg[sizeof(errmsg) - 1] = 0;	/* ensure NULL termination */
	flexfatal(errmsg);
}


/* line_directive_out - spit out a "#line" statement */

void 
line_directive_out(FILE *output_file, int do_infile)
{
	char directive[MAXLINE], filename[MAXLINE];
	char *s1, *s2, *s3;
	static const char *line_fmt = "#line %d \"%s\"\n";

	if (!gen_line_dirs)
		return;

	s1 = do_infile ? infilename : "M4_YY_OUTFILE_NAME";

	if (do_infile && !s1)
		s1 = "<stdin>";

	s2 = filename;
	s3 = &filename[sizeof(filename) - 2];

	while (s2 < s3 && *s1) {
		if (*s1 == '\\')
			/* Escape the '\' */
			*s2++ = '\\';

		*s2++ = *s1++;
	}

	*s2 = '\0';

	if (do_infile)
		snprintf(directive, sizeof(directive), line_fmt, linenum, filename);
	else {
		snprintf(directive, sizeof(directive), line_fmt, 0, filename);
	}

	/*
	 * If output_file is nil then we should put the directive in the
	 * accumulated actions.
	 */
	if (output_file) {
		fputs(directive, output_file);
	} else
		add_action(directive);
}


/* mark_defs1 - mark the current position in the action array as
 *               representing where the user's section 1 definitions end
 *		 and the prolog begins
 */
void 
mark_defs1(void)
{
	defs1_offset = 0;
	action_array[action_index++] = '\0';
	action_offset = prolog_offset = action_index;
	action_array[action_index] = '\0';
}


/* mark_prolog - mark the current position in the action array as
 *               representing the end of the action prolog
 */
void 
mark_prolog(void)
{
	action_array[action_index++] = '\0';
	action_offset = action_index;
	action_array[action_index] = '\0';
}


/* mk2data - generate a data statement for a two-dimensional array
 *
 * Generates a data statement initializing the current 2-D array to "value".
 */
void 
mk2data(int value)
{
	/* short circuit any output */
	if (!gentables)
		return;

	if (datapos >= NUMDATAITEMS) {
		outc(',');
		dataflush();
	}
	if (datapos == 0)
		/* Indent. */
		out("    ");

	else
		outc(',');

	++datapos;

	out_dec("%5d", value);
}


/* mkdata - generate a data statement
 *
 * Generates a data statement initializing the current array element to
 * "value".
 */
void 
mkdata(int value)
{
	/* short circuit any output */
	if (!gentables)
		return;

	if (datapos >= NUMDATAITEMS) {
		outc(',');
		dataflush();
	}
	if (datapos == 0)
		/* Indent. */
		out("    ");
	else
		outc(',');

	++datapos;

	out_dec("%5d", value);
}


/* myctoi - return the integer represented by a string of digits */

int 
myctoi(const char *array)
{
	int val = 0;

	(void) sscanf(array, "%d", &val);

	return val;
}


/* myesc - return character corresponding to escape sequence */

u_char 
myesc(unsigned char array[])
{
	u_char c, esc_char;

	switch (array[1]) {
	case 'b':
		return '\b';
	case 'f':
		return '\f';
	case 'n':
		return '\n';
	case 'r':
		return '\r';
	case 't':
		return '\t';

#if defined (__STDC__)
	case 'a':
		return '\a';
	case 'v':
		return '\v';
#else
	case 'a':
		return '\007';
	case 'v':
		return '\013';
#endif

	case '0':
	case '1':
	case '2':
	case '3':
	case '4':
	case '5':
	case '6':
	case '7':
		{		/* \<octal> */
			int sptr = 1;

			while (isascii(array[sptr]) &&
			    isdigit(array[sptr]))
				/*
				 * Don't increment inside loop control
				 * because if isdigit() is a macro it might
				 * expand into multiple increments ...
				 */
				++sptr;

			c = array[sptr];
			array[sptr] = '\0';

			esc_char = otoi(array + 1);

			array[sptr] = c;

			return esc_char;
		}

	case 'x':
		{		/* \x<hex> */
			int sptr = 2;

			while (isascii(array[sptr]) &&
			    isxdigit(array[sptr]))
				/*
				 * Don't increment inside loop control
				 * because if isdigit() is a macro it might
				 * expand into multiple increments ...
				 */
				++sptr;

			c = array[sptr];
			array[sptr] = '\0';

			esc_char = htoi(array + 2);

			array[sptr] = c;

			return esc_char;
		}

	default:
		return array[1];
	}
}


/* otoi - convert an octal digit string to an integer value */

int 
otoi(unsigned char str[])
{
	unsigned int result;

	(void) sscanf((char *) str, "%o", &result);
	return result;
}


/* out - various flavors of outputting a (possibly formatted) string for the
 *	 generated scanner, keeping track of the line count.
 */

void 
out(const char *str)
{
	fputs(str, stdout);
}

void 
out_dec(const char *fmt, int n)
{
	fprintf(stdout, fmt, n);
}

void 
out_dec2(const char *fmt, int n1, int n2)
{
	fprintf(stdout, fmt, n1, n2);
}

void 
out_hex(const char *fmt, unsigned int x)
{
	fprintf(stdout, fmt, x);
}

void 
out_str(const char *fmt, const char str[])
{
	fprintf(stdout, fmt, str);
}

void 
out_str3(const char *fmt, const char s1[], const char s2[], const char s3[])
{
	fprintf(stdout, fmt, s1, s2, s3);
}

void 
out_str_dec(const char *fmt, const char str[], int n)
{
	fprintf(stdout, fmt, str, n);
}

void 
outc(int c)
{
	fputc(c, stdout);
}

void 
outn(const char *str)
{
	fputs(str, stdout);
	fputc('\n', stdout);
}

/** Print "m4_define( [[def]], [[val]])m4_dnl\n".
 * @param def The m4 symbol to define.
 * @param val The definition; may be NULL.
 * @return buf
 */
void 
out_m4_define(const char *def, const char *val)
{
	const char *fmt = "m4_define( [[%s]], [[%s]])m4_dnl\n";
	fprintf(stdout, fmt, def, val ? val : "");
}


/* readable_form - return the human-readable form of a character
 *
 * The returned string is in static storage.
 */

char *
readable_form(int c)
{
	static char rform[10];

	if ((c >= 0 && c < 32) || c >= 127) {
		switch (c) {
		case '\b':
			return "\\b";
		case '\f':
			return "\\f";
		case '\n':
			return "\\n";
		case '\r':
			return "\\r";
		case '\t':
			return "\\t";

#if defined (__STDC__)
		case '\a':
			return "\\a";
		case '\v':
			return "\\v";
#endif

		default:
			snprintf(rform, sizeof(rform), "\\%.3o", (unsigned int) c);
			return rform;
		}
	} else if (c == ' ')
		return "' '";

	else {
		rform[0] = c;
		rform[1] = '\0';

		return rform;
	}
}


/* reallocate_array - increase the size of a dynamic array */

void *
reallocate_array(void *array, int size, size_t element_size)
{
	void *new_array;
	size_t num_bytes = element_size * size;

	new_array = realloc(array, num_bytes);
	if (!new_array)
		flexfatal(_("attempt to increase array size failed"));

	return new_array;
}


/* skelout - write out one section of the skeleton file
 *
 * Description
 *    Copies skelfile or skel array to stdout until a line beginning with
 *    "%%" or EOF is found.
 */
void 
skelout(void)
{
	char buf_storage[MAXLINE];
	char *buf = buf_storage;
	bool do_copy = true;

	/* "reset" the state by clearing the buffer and pushing a '1' */
	if (sko_len > 0)
		sko_peek(&do_copy);
	sko_len = 0;
	sko_push(do_copy = true);


	/*
	 * Loop pulling lines either from the skelfile, if we're using one,
	 * or from the skel[] array.
	 */
	while (skelfile ?
	    (fgets(buf, MAXLINE, skelfile) != NULL) :
	    ((buf = (char *) skel[skel_ind++]) != 0)) {

		if (skelfile)
			chomp(buf);

		/* copy from skel array */
		if (buf[0] == '%') {	/* control line */
			/* print the control line as a comment. */
			if (ddebug && buf[1] != '#') {
				if (buf[strlen(buf) - 1] == '\\')
					out_str("/* %s */\\\n", buf);
				else
					out_str("/* %s */\n", buf);
			}
			/*
			 * We've been accused of using cryptic markers in the
			 * skel. So we'll use
			 * emacs-style-hyphenated-commands. We might consider
			 * a hash if this if-else-if-else chain gets too
			 * large.
			 */
#define cmd_match(s) (strncmp(buf,(s),strlen(s))==0)

			if (buf[1] == '%') {
				/* %% is a break point for skelout() */
				return;
			} else if (cmd_match(CMD_PUSH)) {
				sko_push(do_copy);
				if (ddebug) {
					out_str("/*(state = (%s) */", do_copy ? "true" : "false");
				}
				out_str("%s\n", buf[strlen(buf) - 1] == '\\' ? "\\" : "");
			} else if (cmd_match(CMD_POP)) {
				sko_pop(&do_copy);
				if (ddebug) {
					out_str("/*(state = (%s) */", do_copy ? "true" : "false");
				}
				out_str("%s\n", buf[strlen(buf) - 1] == '\\' ? "\\" : "");
			} else if (cmd_match(CMD_IF_REENTRANT)) {
				sko_push(do_copy);
				do_copy = reentrant && do_copy;
			} else if (cmd_match(CMD_IF_NOT_REENTRANT)) {
				sko_push(do_copy);
				do_copy = !reentrant && do_copy;
			} else if (cmd_match(CMD_IF_BISON_BRIDGE)) {
				sko_push(do_copy);
				do_copy = bison_bridge_lval && do_copy;
			} else if (cmd_match(CMD_IF_NOT_BISON_BRIDGE)) {
				sko_push(do_copy);
				do_copy = !bison_bridge_lval && do_copy;
			} else if (cmd_match(CMD_ENDIF)) {
				sko_pop(&do_copy);
			} else if (cmd_match(CMD_IF_TABLES_SER)) {
				do_copy = do_copy && tablesext;
			} else if (cmd_match(CMD_TABLES_YYDMAP)) {
				if (tablesext && yydmap_buf.elts)
					outn((char *) (yydmap_buf.elts));
			} else if (cmd_match(CMD_DEFINE_YYTABLES)) {
				out_str("#define YYTABLES_NAME \"%s\"\n",
				    tablesname ? tablesname : "yytables");
			} else if (cmd_match(CMD_IF_CPP_ONLY)) {
				/* only for C++ */
				sko_push(do_copy);
				do_copy = C_plus_plus;
			} else if (cmd_match(CMD_IF_C_ONLY)) {
				/* %- only for C */
				sko_push(do_copy);
				do_copy = !C_plus_plus;
			} else if (cmd_match(CMD_IF_C_OR_CPP)) {
				/* %* for C and C++ */
				sko_push(do_copy);
				do_copy = true;
			} else if (cmd_match(CMD_NOT_FOR_HEADER)) {
				/* %c begin linkage-only (non-header) code. */
				OUT_BEGIN_CODE();
			} else if (cmd_match(CMD_OK_FOR_HEADER)) {
				/* %e end linkage-only code. */
				OUT_END_CODE();
			} else if (buf[1] == '#') {
				/* %# a comment in the skel. ignore. */
			} else {
				flexfatal(_("bad line in skeleton file"));
			}
		} else if (do_copy)
			outn(buf);
	}			/* end while */
}


/* transition_struct_out - output a yy_trans_info structure
 *
 * outputs the yy_trans_info structure with the two elements, element_v and
 * element_n.  Formats the output with spaces and carriage returns.
 */

void 
transition_struct_out(int element_v, int element_n)
{

	/* short circuit any output */
	if (!gentables)
		return;

	out_dec2(" {%4d,%4d },", element_v, element_n);

	datapos += TRANS_STRUCT_PRINT_LENGTH;

	if (datapos >= 79 - TRANS_STRUCT_PRINT_LENGTH) {
		outc('\n');

		if (++dataline % 10 == 0)
			outc('\n');

		datapos = 0;
	}
}


/* The following is only needed when building flex's parser using certain
 * broken versions of bison.
 */
void *
yy_flex_xmalloc(int size)
{
	void *result = malloc((size_t) size);

	if (!result)
		flexfatal(_
		    ("memory allocation failed in yy_flex_xmalloc()"));

	return result;
}


/* Remove all '\n' and '\r' characters, if any, from the end of str.
 * str can be any null-terminated string, or NULL.
 * returns str. */
char *
chomp(char *str)
{
	char *p = str;

	if (!str || !*str)	/* s is null or empty string */
		return str;

	/* find end of string minus one */
	while (*p)
		++p;
	--p;

	/* eat newlines */
	while (p >= str && (*p == '\r' || *p == '\n'))
		*p-- = 0;
	return str;
}