BLI_dynstr.c

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/*
 * $Id: BLI_dynstr.c 35246 2011-02-27 20:37:56Z jesterking $
 *
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 * Dynamically sized string ADT
 */

#include <stdarg.h>
#include <string.h>

#include "MEM_guardedalloc.h"
#include "BLI_blenlib.h"
#include "BLI_dynstr.h"

#ifdef _WIN32
#ifndef vsnprintf
#define vsnprintf _vsnprintf
#endif
#endif

#ifndef va_copy
# ifdef __va_copy
#  define va_copy(a,b) __va_copy(a,b)
# else /* !__va_copy */
#  define va_copy(a,b) ((a)=(b))
# endif /* __va_copy */
#endif /* va_copy */

/***/

typedef struct DynStrElem DynStrElem;
struct DynStrElem {
        DynStrElem *next;
        
        char *str;
};

struct DynStr {
        DynStrElem *elems, *last;
        int curlen;
};

/***/

DynStr *BLI_dynstr_new(void) {
        DynStr *ds= MEM_mallocN(sizeof(*ds), "DynStr");
        ds->elems= ds->last= NULL;
        ds->curlen= 0;
        
        return ds;
}

void BLI_dynstr_append(DynStr *ds, const char *cstr) {
        DynStrElem *dse= malloc(sizeof(*dse));
        int cstrlen= strlen(cstr);
        
        dse->str= malloc(cstrlen+1);
        memcpy(dse->str, cstr, cstrlen+1);
        dse->next= NULL;
        
        if (!ds->last)
                ds->last= ds->elems= dse;
        else
                ds->last= ds->last->next= dse;

        ds->curlen+= cstrlen;
}

void BLI_dynstr_nappend(DynStr *ds, const char *cstr, int len) {
        DynStrElem *dse= malloc(sizeof(*dse));
        int cstrlen= BLI_strnlen(cstr, len);

        dse->str= malloc(cstrlen+1);
        memcpy(dse->str, cstr, cstrlen);
        dse->str[cstrlen] = '\0';
        dse->next= NULL;

        if (!ds->last)
                ds->last= ds->elems= dse;
        else
                ds->last= ds->last->next= dse;

        ds->curlen+= cstrlen;
}

void BLI_dynstr_vappendf(DynStr *ds, const char *format, va_list args)
{
        char *message, fixedmessage[256];
        int len= sizeof(fixedmessage);
        const int maxlen= 65536;
        int retval;

        while(1) {
                va_list args_cpy;
                if(len == sizeof(fixedmessage))
                        message= fixedmessage;
                else
                        message= MEM_callocN(sizeof(char) * len, "BLI_dynstr_appendf");

                /* cant reuse the same args, so work on a copy */
                va_copy(args_cpy, args);
                retval= vsnprintf(message, len, format, args_cpy);
                va_end(args_cpy);

                if(retval == -1) {
                        /* -1 means not enough space, but on windows it may also mean
                         * there is a formatting error, so we impose a maximum length */
                        if(message != fixedmessage)
                                MEM_freeN(message);
                        message= NULL;

                        len *= 2;
                        if(len > maxlen) {
                                fprintf(stderr, "BLI_dynstr_append text too long or format error.\n");
                                break;
                        }
                }
                else if(retval >= len) {
                        /* in C99 the actual length required is returned */
                        if(message != fixedmessage)
                                MEM_freeN(message);
                        message= NULL;

                        /* retval doesnt include \0 terminator */
                        len= retval + 1;
                }
                else
                        break;
        }

        if(message) {
                BLI_dynstr_append(ds, message);

                if(message != fixedmessage)
                        MEM_freeN(message);
        }
}

void BLI_dynstr_appendf(DynStr *ds, const char *format, ...)
{
        va_list args;
        char *message, fixedmessage[256];
        int len= sizeof(fixedmessage);
        const int maxlen= 65536;
        int retval;

        /* note that it's tempting to just call BLI_dynstr_vappendf here
         * and avoid code duplication, that crashes on some system because
         * va_start/va_end have to be called for each vsnprintf call */

        while(1) {
                if(len == sizeof(fixedmessage))
                        message= fixedmessage;
                else
                        message= MEM_callocN(sizeof(char)*(len), "BLI_dynstr_appendf");

                va_start(args, format);
                retval= vsnprintf(message, len, format, args);
                va_end(args);

                if(retval == -1) {
                        /* -1 means not enough space, but on windows it may also mean
                         * there is a formatting error, so we impose a maximum length */
                        if(message != fixedmessage)
                                MEM_freeN(message);
                        message= NULL;

                        len *= 2;
                        if(len > maxlen) {
                                fprintf(stderr, "BLI_dynstr_append text too long or format error.\n");
                                break;
                        }
                }
                else if(retval >= len) {
                        /* in C99 the actual length required is returned */
                        if(message != fixedmessage)
                                MEM_freeN(message);
                        message= NULL;

                        /* retval doesnt include \0 terminator */
                        len= retval + 1;
                }
                else
                        break;
        }

        if(message) {
                BLI_dynstr_append(ds, message);

                if(message != fixedmessage)
                        MEM_freeN(message);
        }
}

int BLI_dynstr_get_len(DynStr *ds) {
        return ds->curlen;
}

char *BLI_dynstr_get_cstring(DynStr *ds) {
        char *s, *rets= MEM_mallocN(ds->curlen+1, "dynstr_cstring");
        DynStrElem *dse;
        
        for (s= rets, dse= ds->elems; dse; dse= dse->next) {
                int slen= strlen(dse->str);

                memcpy(s, dse->str, slen);

                s+= slen;
        }
        rets[ds->curlen]= '\0';
        
        return rets;
}

void BLI_dynstr_free(DynStr *ds) {
        DynStrElem *dse;
        
        for (dse= ds->elems; dse; ) {
                DynStrElem *n= dse->next;
                
                free(dse->str);
                free(dse);
                
                dse= n;
        }
        
        MEM_freeN(ds);
}