source: trunk/src/kmk/for.c@ 22

/*
 * Copyright (c) 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Christos Zoulas.
 *
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. 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 BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * @(#)for.c    8.1 (Berkeley) 6/6/93
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/usr.bin/make/for.c,v 1.19 2002/10/09 03:42:10 jmallett Exp $");

/*-
 * for.c --
 *      Functions to handle loops in a makefile.
 *
 * Interface:
 *      For_Eval        Evaluate the loop in the passed line.
 *      For_Run         Run accumulated loop
 *
 */

#include    <ctype.h>
#include    "make.h"
#include    "hash.h"
#include    "dir.h"
#include    "buf.h"

/*
 * For statements are of the form:
 *
 * .for <variable> in <varlist>
 * ...
 * .endfor
 *
 * The trick is to look for the matching end inside for for loop
 * To do that, we count the current nesting level of the for loops.
 * and the .endfor statements, accumulating all the statements between
 * the initial .for loop and the matching .endfor;
 * then we evaluate the for loop for each variable in the varlist.
 */

static int        forLevel = 0;         /* Nesting level        */
static char      *forVar;               /* Iteration variable   */
static Buffer     forBuf;               /* Commands in loop     */
static Lst        forLst;               /* List of items        */

/*
 * State of a for loop.
 */
typedef struct _For {
    Buffer        buf;                  /* Unexpanded buffer    */
    char*         var;                  /* Index name           */
    Lst           lst;                  /* List of variables    */
} For;

static int ForExec(void *, void *);





/*-
 *-----------------------------------------------------------------------
 * For_Eval --
 *      Evaluate the for loop in the passed line. The line
 *      looks like this:
 *          .for <variable> in <varlist>
 *
 * Results:
 *      TRUE: We found a for loop, or we are inside a for loop
 *      FALSE: We did not find a for loop, or we found the end of the for
 *             for loop.
 *
 * Side Effects:
 *      None.
 *
 *-----------------------------------------------------------------------
 */
int
For_Eval (char *line)
{
    char            *ptr = line, *sub, *wrd;
    int             level;      /* Level at which to report errors. */

    level = PARSE_FATAL;


    if (forLevel == 0) {
        Buffer      buf;
        int         varlen;

        for (ptr++; *ptr && isspace((unsigned char) *ptr); ptr++)
            continue;
        /*
         * If we are not in a for loop quickly determine if the statement is
         * a for.
         */
        if (ptr[0] != 'f' || ptr[1] != 'o' || ptr[2] != 'r' ||
            !isspace((unsigned char) ptr[3]))
            return FALSE;
        ptr += 3;

        /*
         * we found a for loop, and now we are going to parse it.
         */
        while (*ptr && isspace((unsigned char) *ptr))
            ptr++;

        /*
         * Grab the variable
         */
        buf = Buf_Init(0);
        for (wrd = ptr; *ptr && !isspace((unsigned char) *ptr); ptr++)
            continue;
        Buf_AddBytes(buf, ptr - wrd, (Byte *) wrd);

        forVar = (char *) Buf_GetAll(buf, &varlen);
        if (varlen == 0) {
            Parse_Error (level, "missing variable in for");
            return 0;
        }
        Buf_Destroy(buf, FALSE);

        while (*ptr && isspace((unsigned char) *ptr))
            ptr++;

        /*
         * Grab the `in'
         */
        if (ptr[0] != 'i' || ptr[1] != 'n' ||
            !isspace((unsigned char) ptr[2])) {
            Parse_Error (level, "missing `in' in for");
            printf("%s\n", ptr);
            return 0;
        }
        ptr += 3;

        while (*ptr && isspace((unsigned char) *ptr))
            ptr++;

        /*
         * Make a list with the remaining words
         */
        forLst = Lst_Init(FALSE);
        buf = Buf_Init(0);
        sub = Var_Subst(NULL, ptr, VAR_GLOBAL, FALSE);

#define ADDWORD() \
        Buf_AddBytes(buf, ptr - wrd, (Byte *) wrd), \
        Buf_AddByte(buf, (Byte) '\0'), \
        Lst_AtFront(forLst, (void *) Buf_GetAll(buf, &varlen)), \
        Buf_Destroy(buf, FALSE)

        for (ptr = sub; *ptr && isspace((unsigned char) *ptr); ptr++)
            continue;

        for (wrd = ptr; *ptr; ptr++)
            if (isspace((unsigned char) *ptr)) {
                ADDWORD();
                buf = Buf_Init(0);
                while (*ptr && isspace((unsigned char) *ptr))
                    ptr++;
                wrd = ptr--;
            }
        DEBUGF(FOR, ("For: Iterator %s List %s\n", forVar, sub));
        if (ptr - wrd > 0)
            ADDWORD();
        else
            Buf_Destroy(buf, TRUE);
        free(sub);

        forBuf = Buf_Init(0);
        forLevel++;
        return 1;
    }
    else if (*ptr == '.') {

        for (ptr++; *ptr && isspace((unsigned char) *ptr); ptr++)
            continue;

        if (strncmp(ptr, "endfor", 6) == 0 &&
            (isspace((unsigned char) ptr[6]) || !ptr[6])) {
            DEBUGF(FOR, ("For: end for %d\n", forLevel));
            if (--forLevel < 0) {
                Parse_Error (level, "for-less endfor");
                return 0;
            }
        }
        else if (strncmp(ptr, "for", 3) == 0 &&
                 isspace((unsigned char) ptr[3])) {
            forLevel++;
            DEBUGF(FOR, ("For: new loop %d\n", forLevel));
        }
    }

    if (forLevel != 0) {
        Buf_AddBytes(forBuf, strlen(line), (Byte *) line);
        Buf_AddByte(forBuf, (Byte) '\n');
        return 1;
    }
    else {
        return 0;
    }
}

/*-
 *-----------------------------------------------------------------------
 * ForExec --
 *      Expand the for loop for this index and push it in the Makefile
 *
 * Results:
 *      None.
 *
 * Side Effects:
 *      None.
 *
 *-----------------------------------------------------------------------
 */
static int
ForExec(void *namep, void *argp)
{
    char *name = (char *) namep;
    For *arg = (For *) argp;
    int len;
    Var_Set(arg->var, name, VAR_GLOBAL);
    DEBUGF(FOR, ("--- %s = %s\n", arg->var, name));
    Parse_FromString(Var_Subst(arg->var, (char *) Buf_GetAll(arg->buf, &len),
                               VAR_GLOBAL, FALSE));
    Var_Delete(arg->var, VAR_GLOBAL);

    return 0;
}



/*-
 *-----------------------------------------------------------------------
 * For_Run --
 *      Run the for loop, immitating the actions of an include file
 *
 * Results:
 *      None.
 *
 * Side Effects:
 *      None.
 *
 *-----------------------------------------------------------------------
 */
void
For_Run(void)
{
    For arg;

    if (forVar == NULL || forBuf == NULL || forLst == NULL)
        return;
    arg.var = forVar;
    arg.buf = forBuf;
    arg.lst = forLst;
    forVar = NULL;
    forBuf = NULL;
    forLst = NULL;

    Lst_ForEach(arg.lst, ForExec, (void *) &arg);

    free(arg.var);
    Lst_Destroy(arg.lst, (void (*)(void *)) free);
    Buf_Destroy(arg.buf, TRUE);
}