/* $OpenBSD: safe_sprintf.c,v 1.7 2023/10/17 09:52:09 nicm Exp $ */

/****************************************************************************
 * Copyright 2018-2020,2021 Thomas E. Dickey                                *
 * Copyright 1998-2012,2013 Free Software Foundation, Inc.                  *
 *                                                                          *
 * Permission is hereby granted, free of charge, to any person obtaining a  *
 * copy of this software and associated documentation files (the            *
 * "Software"), to deal in the Software without restriction, including      *
 * without limitation the rights to use, copy, modify, merge, publish,      *
 * distribute, distribute with modifications, sublicense, and/or sell       *
 * copies of the Software, and to permit persons to whom the Software is    *
 * furnished to do so, subject to the following conditions:                 *
 *                                                                          *
 * The above copyright notice and this permission notice shall be included  *
 * in all copies or substantial portions of the Software.                   *
 *                                                                          *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
 *                                                                          *
 * Except as contained in this notice, the name(s) of the above copyright   *
 * holders shall not be used in advertising or otherwise to promote the     *
 * sale, use or other dealings in this Software without prior written       *
 * authorization.                                                           *
 ****************************************************************************/

/****************************************************************************
 *  Author: Thomas E. Dickey        1997-on                                 *
 ****************************************************************************/

#include <curses.priv.h>
#include <ctype.h>

MODULE_ID("$Id: safe_sprintf.c,v 1.7 2023/10/17 09:52:09 nicm Exp $")

#if USE_SAFE_SPRINTF

typedef enum {
    Flags, Width, Prec, Type, Format
} PRINTF;

#define VA_INTGR(type) ival = (int) va_arg(ap, type)
#define VA_FLOAT(type) fval = va_arg(ap, type)
#define VA_POINT(type) pval = (void *)va_arg(ap, type)

/*
 * Scan a variable-argument list for printf to determine the number of
 * characters that would be emitted.
 */
static int
_nc_printf_length(const char *fmt, va_list ap)
{
    size_t length = BUFSIZ;
    char *buffer;
    char *format;
    int len = 0;
    size_t fmt_len;
    char fmt_arg[BUFSIZ];

    if (fmt == 0 || *fmt == '\0')
        return 0;
    fmt_len = strlen(fmt) + 1;
    if ((format = typeMalloc(char, fmt_len)) == 0)
          return -1;
    if ((buffer = typeMalloc(char, length)) == 0) {
        free(format);
        return -1;
    }

    while (*fmt != '\0') {
        if (*fmt == '%') {
            static char dummy[] = "";
            PRINTF state = Flags;
            char *pval = dummy; /* avoid const-cast */
            double fval = 0.0;
            int done = FALSE;
            int ival = 0;
            int prec = -1;
            int type = 0;
            int used = 0;
            int width = -1;
            size_t f = 0;

            format[f++] = *fmt;
            while (*++fmt != '\0' && len >= 0 && !done) {
                format[f++] = *fmt;

                if (isdigit(UChar(*fmt))) {
                    int num = *fmt - '0';
                    if (state == Flags && num != 0)
                        state = Width;
                    if (state == Width) {
                        if (width < 0)
                            width = 0;
                        width = (width * 10) + num;
                    } else if (state == Prec) {
                        if (prec < 0)
                            prec = 0;
                        prec = (prec * 10) + num;
                    }
                } else if (*fmt == '*') {
                    VA_INTGR(int);
                    if (state == Flags)
                        state = Width;
                    if (state == Width) {
                        width = ival;
                    } else if (state == Prec) {
                        prec = ival;
                    }
                    _nc_SPRINTF(fmt_arg,
                                _nc_SLIMIT(sizeof(fmt_arg))
                                "%d", ival);
                    fmt_len += strlen(fmt_arg);
                    if ((format = _nc_doalloc(format, fmt_len)) == 0) {
                        free(buffer);
                        return -1;
                    }
                    --f;
                    _nc_STRCPY(&format[f], fmt_arg, fmt_len - f);
                    f = strlen(format);
                } else if (isalpha(UChar(*fmt))) {
                    done = TRUE;
                    switch (*fmt) {
                    case 'Z':   /* FALLTHRU */
                    case 'h':   /* FALLTHRU */
                    case 'l':   /* FALLTHRU */
                        done = FALSE;
                        type = *fmt;
                        break;
                    case 'i':   /* FALLTHRU */
                    case 'd':   /* FALLTHRU */
                    case 'u':   /* FALLTHRU */
                    case 'x':   /* FALLTHRU */
                    case 'X':   /* FALLTHRU */
                        if (type == 'l')
                            VA_INTGR(long);
                        else if (type == 'Z')
                            VA_INTGR(size_t);
                        else
                            VA_INTGR(int);
                        used = 'i';
                        break;
                    case 'f':   /* FALLTHRU */
                    case 'e':   /* FALLTHRU */
                    case 'E':   /* FALLTHRU */
                    case 'g':   /* FALLTHRU */
                    case 'G':   /* FALLTHRU */
                        VA_FLOAT(double);
                        used = 'f';
                        break;
                    case 'c':
                        VA_INTGR(int);
                        used = 'i';
                        break;
                    case 's':
                        VA_POINT(char *);
                        if (prec < 0)
                            prec = (int) strlen(pval);
                        if (prec > (int) length) {
                            length = length + (size_t) prec;
                            buffer = typeRealloc(char, length, buffer);
                            if (buffer == 0) {
                                free(format);
                                return -1;
                            }
                        }
                        used = 'p';
                        break;
                    case 'p':
                        VA_POINT(void *);
                        used = 'p';
                        break;
                    case 'n':
                        VA_POINT(int *);
                        used = 0;
                        break;
                    default:
                        break;
                    }
                } else if (*fmt == '.') {
                    state = Prec;
                } else if (*fmt == '%') {
                    done = TRUE;
                    used = 'p';
                }
            }
            format[f] = '\0';
            switch (used) {
            case 'i':
                _nc_SPRINTF(buffer, _nc_SLIMIT(length) format, ival);
                break;
            case 'f':
                _nc_SPRINTF(buffer, _nc_SLIMIT(length) format, fval);
                break;
            default:
                _nc_SPRINTF(buffer, _nc_SLIMIT(length) format, pval);
                break;
            }
            len += (int) strlen(buffer);
        } else {
            fmt++;
            len++;
        }
    }

    free(buffer);
    free(format);
    return len;
}
#endif

#define my_buffer _nc_globals.safeprint_buf
#define my_length _nc_globals.safeprint_used

/*
 * Wrapper for vsprintf that allocates a buffer big enough to hold the result.
 */
NCURSES_EXPORT(char *)
NCURSES_SP_NAME(_nc_printf_string) (NCURSES_SP_DCLx
                                    const char *fmt,
                                    va_list ap)
{
    char *result = NULL;

    if (SP_PARM != NULL && fmt != NULL) {
#if USE_SAFE_SPRINTF
        va_list ap2;
        int len;

        begin_va_copy(ap2, ap);
        len = _nc_printf_length(fmt, ap2);
        end_va_copy(ap2);

        if ((int) my_length < len + 1) {
            my_length = (size_t) (2 * (len + 1));
            my_buffer = typeRealloc(char, my_length, my_buffer);
        }
        if (my_buffer != NULL) {
            *my_buffer = '\0';
            if (len >= 0) {
                vsprintf(my_buffer, fmt, ap);
            }
            result = my_buffer;
        }
#else
#define MyCols _nc_globals.safeprint_cols
#define MyRows _nc_globals.safeprint_rows

        if (screen_lines(SP_PARM) > MyRows || screen_columns(SP_PARM) > MyCols) {
            if (screen_lines(SP_PARM) > MyRows)
                MyRows = screen_lines(SP_PARM);
            if (screen_columns(SP_PARM) > MyCols)
                MyCols = screen_columns(SP_PARM);
            my_length = (size_t) (MyRows * (MyCols + 1)) + 1;
            if (my_length < 80)
                my_length = 80;
            my_buffer = typeRealloc(char, my_length, my_buffer);
        }

        if (my_buffer != NULL) {
# if HAVE_VSNPRINTF
            /* SUSv2, 1997 */
            int used;
            while ((used = vsnprintf(my_buffer, my_length, fmt, ap))
                   >= (int) my_length) {
                my_length = (size_t) ((3 * used) / 2);
                my_buffer = typeRealloc(char, my_length, my_buffer);
            }
# else
            /* ISO/ANSI C, 1989 */
            vsprintf(my_buffer, fmt, ap);
# endif
            result = my_buffer;
        }
#endif
    } else if (my_buffer != NULL) {     /* see _nc_freeall() */
        free(my_buffer);
        my_buffer = NULL;
        my_length = 0;
    }
    return result;
}

#if NCURSES_SP_FUNCS
NCURSES_EXPORT(char *)
_nc_printf_string(const char *fmt, va_list ap)
{
    return NCURSES_SP_NAME(_nc_printf_string) (CURRENT_SCREEN, fmt, ap);
}
#endif