source: nanovis/trunk/Switch.cpp @ 4596

/* -*- mode: c++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
 * Switch.cpp --
 *
 * This module implements command/argument switch parsing procedures for the
 * BLT toolkit.
 *
 *      Copyright 1991-2004 George A Howlett.
 *
 *      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, 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 AUTHORS OR 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.
 */

#include <assert.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>
#include <malloc.h>
#include <tcl.h>
#include "Switch.h"

namespace nv {

static void
DoHelp(Tcl_Interp *interp, SwitchSpec *specs)
{
    Tcl_DString ds;
    SwitchSpec *sp;

    Tcl_DStringInit(&ds);
    Tcl_DStringAppend(&ds, "following switches are available:", -1);
    for (sp = specs; sp->type != SWITCH_END; sp++) {
        Tcl_DStringAppend(&ds, "\n    ", 4);
        Tcl_DStringAppend(&ds, sp->switchName, -1);
        Tcl_DStringAppend(&ds, " ", 1);
        Tcl_DStringAppend(&ds, sp->help, -1);
    }
    Tcl_AppendResult(interp, Tcl_DStringValue(&ds), (char *)NULL);
    Tcl_DStringFree(&ds);
}

/*
 *---------------------------------------------------------------------------
 *
 * FindSwitchSpec --
 *
 *      Search through a table of configuration specs, looking for one that
 *      matches a given argvName.
 *
 * Results:
 *      The return value is a pointer to the matching entry, or NULL if
 *      nothing matched.  In that case an error message is left in the
 *      interp's result.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */
static SwitchSpec *
FindSwitchSpec(
    Tcl_Interp *interp,         /* Used for reporting errors. */
    SwitchSpec *specs,          /* Pointer to table of configuration
                                 * specifications for a widget. */
    const char *name,           /* Name identifying a particular switch. */
    int length,                 /* Length of name. */
    int needFlags,              /* Flags that must be present in matching
                                 * entry. */
    int hateFlags)              /* Flags that must NOT be present in matching
                                 * entry. */
{
    SwitchSpec *sp;
    char c;                     /* First character of current argument. */
    SwitchSpec *matchPtr;       /* Matching spec, or NULL. */

    c = name[1];
    matchPtr = NULL;
    for (sp = specs; sp->type != SWITCH_END; sp++) {
        if (sp->switchName == NULL) {
            continue;
        }
        if (((sp->flags & needFlags) != needFlags) || (sp->flags & hateFlags)) {
            continue;
        }
        if ((sp->switchName[1] != c) || 
            (strncmp(sp->switchName, name, length) != 0)) {
            continue;
        }
        if (sp->switchName[length] == '\0') {
            return sp;          /* Stop on a perfect match. */
        }
        if (matchPtr != NULL) {
            Tcl_AppendResult(interp, "ambiguous switch \"", name, "\"\n", 
                (char *) NULL);
            DoHelp(interp, specs);
            return NULL;
        }
        matchPtr = sp;
    }
    if (strcmp(name, "-help") == 0) {
        DoHelp(interp, specs);
        return NULL;
    }
    if (matchPtr == NULL) {
        Tcl_AppendResult(interp, "unknown switch \"", name, "\"\n", 
                         (char *)NULL);
        DoHelp(interp, specs);
        return NULL;
    }
    return matchPtr;
}

/*
 *---------------------------------------------------------------------------
 *
 * DoSwitch --
 *
 *      This procedure applies a single configuration switch to a widget
 *      record.
 *
 * Results:
 *      A standard Tcl return value.
 *
 * Side effects:
 *      WidgRec is modified as indicated by specPtr and value.  The old value
 *      is recycled, if that is appropriate for the value type.
 *
 *---------------------------------------------------------------------------
 */
static int
DoSwitch(
    Tcl_Interp *interp,         /* Interpreter for error reporting. */
    SwitchSpec *sp,             /* Specifier to apply. */
    Tcl_Obj *objPtr,            /* Value to use to fill in widgRec. */
    void *record)               /* Record whose fields are to be modified.
                                 * Values must be properly initialized. */
{
    do {
        char *ptr;

        ptr = (char *)record + sp->offset;
        switch (sp->type) {
        case SWITCH_BOOLEAN:
            {
                int value;

                if (Tcl_GetBooleanFromObj(interp, objPtr, &value) != TCL_OK) {
                    return TCL_ERROR;
                }
                if (sp->mask > 0) {
                    if (value) {
                        *((int *)ptr) |= sp->mask;
                    } else {
                        *((int *)ptr) &= ~sp->mask;
                    }
                } else {
                    *((int *)ptr) = value;
                }
            }
            break;

        case SWITCH_DOUBLE:
            if (Tcl_GetDoubleFromObj(interp, objPtr, (double *)ptr) != TCL_OK) {
                return TCL_ERROR;
            }
            break;

        case SWITCH_OBJ:
            *(Tcl_Obj **)ptr = objPtr;
            break;

        case SWITCH_FLOAT:
            {
                double value;

                if (Tcl_GetDoubleFromObj(interp, objPtr, &value) != TCL_OK) {
                    return TCL_ERROR;
                }
                *(float *)ptr = (float)value;
            }
            break;

        case SWITCH_INT:
            if (Tcl_GetIntFromObj(interp, objPtr, (int *)ptr) != TCL_OK) {
                return TCL_ERROR;
            }
            break;

        case SWITCH_LIST:
            {
                int argc;

                if (Tcl_SplitList(interp, Tcl_GetString(objPtr), &argc, 
                                  (const char ***)ptr) != TCL_OK) {
                    return TCL_ERROR;
                }
            }
            break;

        case SWITCH_LONG:
            if (Tcl_GetLongFromObj(interp, objPtr, (long *)ptr) != TCL_OK) {
                return TCL_ERROR;
            }
            break;

        case SWITCH_STRING: 
            {
                char *oldPtr, *newPtr, **strPtr;
                char *string;

                string = Tcl_GetString(objPtr);
                strPtr = (char **)ptr;
                newPtr = ((*string == '\0') && (sp->flags & SWITCH_NULL_OK))
                    ? NULL : strdup(string);
                oldPtr = *strPtr;
                if (oldPtr != NULL) {
                    free(oldPtr);
                }
                *strPtr = newPtr;
            }
            break;

        case SWITCH_CUSTOM:
            assert(sp->customPtr != NULL);
            if ((*sp->customPtr->parseProc)(sp->customPtr->clientData, interp,
                sp->switchName, objPtr, (char *)record, sp->offset, sp->flags) 
                != TCL_OK) {
                return TCL_ERROR;
            }
            break;

        default: 
            Tcl_AppendResult(interp, "bad switch table: unknown type", 
                             (char *)NULL);
            return TCL_ERROR;
        }
        sp++;
    } while ((sp->switchName == NULL) && (sp->type != SWITCH_END));
    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * ParseSwitches --
 *
 *      Process command-line switches to fill in fields of a record with
 *      resources and other parameters.
 *
 * Results:
 *      Returns the number of arguments comsumed by parsing the command line.
 *      If an error occurred, -1 will be returned and an error messages can be
 *      found as the interpreter result.
 *
 * Side effects:
 *      The fields of widgRec get filled in with information from argc/argv.
 *      Old information in widgRec's fields gets recycled.
 *
 *---------------------------------------------------------------------------
 */
int
ParseSwitches(
    Tcl_Interp *interp,         /* Interpreter for error reporting. */
    SwitchSpec *specs,          /* Describes legal switches. */
    int objc,                   /* Number of elements in argv. */
    Tcl_Obj *const *objv,       /* Command-line switches. */
    void *record,               /* Record whose fields are to be modified.
                                 * Values must be properly initialized. */
    int flags)                  /* Used to specify additional flags that must
                                 * be present in switch specs for them to be
                                 * considered.  */
{
    SwitchSpec *sp;
    int count;
    int needFlags;              /* Specs must contain this set of flags or
                                 * else they are not considered. */
    int hateFlags;              /* If a spec contains any bits here, it's not
                                 * considered. */

    needFlags = flags & ~(SWITCH_USER_BIT - 1);
    hateFlags = 0;

    /*
     * Pass 1:  Clear the change flags on all the specs so that we 
     *          can check it later.
     */
    for (sp = specs; sp->type != SWITCH_END; sp++) {
        sp->flags &= ~SWITCH_SPECIFIED;
    }
    /*
     * Pass 2:  Process the arguments that match entries in the specs.
     *          It's an error if the argument doesn't match anything.
     */
    for (count = 0; count < objc; count++) {
        char *arg;
        int length;

        arg = Tcl_GetStringFromObj(objv[count], &length);
        if (flags & SWITCH_OBJV_PARTIAL) {
            /* 
             * If the argument doesn't start with a '-' (not a switch) or is
             * '--', stop processing and return the number of arguments
             * comsumed.
             */
            if (arg[0] != '-') {
                return count;
            }
            if ((arg[1] == '-') && (arg[2] == '\0')) {
                return count + 1; /* include the "--" in the count. */
            }
        }
        sp = FindSwitchSpec(interp, specs, arg, length, needFlags, hateFlags);
        if (sp == NULL) {
            return -1;
        }
        if (sp->type == SWITCH_BITMASK) {
            char *ptr;

            ptr = (char *)record + sp->offset;
            *((int *)ptr) |= sp->mask;
        } else if (sp->type == SWITCH_BITMASK_NEG) {
            char *ptr;
            
            ptr = (char *)record + sp->offset;
            *((int *)ptr) &= ~sp->mask;
        } else if (sp->type == SWITCH_VALUE) {
            char *ptr;
            
            ptr = (char *)record + sp->offset;
            *((int *)ptr) = sp->mask;
        } else {
            count++;
            if (count == objc) {
                Tcl_AppendResult(interp, "value for \"", arg, "\" missing", 
                                 (char *) NULL);
                return -1;
            }
            if (DoSwitch(interp, sp, objv[count], record) != TCL_OK) {
                char msg[200];

                sprintf(msg, "\n    (processing \"%.40s\" switch)", 
                        sp->switchName);
                Tcl_AddErrorInfo(interp, msg);
                return -1;
            }
        }
        sp->flags |= SWITCH_SPECIFIED;
    }
    return count;
}

/*
 *---------------------------------------------------------------------------
 *
 * FreeSwitches --
 *
 *      Free up all resources associated with switches.
 *
 * Results:
 *      None.
 *
 *---------------------------------------------------------------------------
 */
void
FreeSwitches(
    SwitchSpec *specs,          /* Describes legal switches. */
    void *record,               /* Record whose fields contain current values
                                 * for switches. */
    int needFlags)              /* Used to specify additional flags that must
                                 * be present in config specs for them to be
                                 * considered. */
{
    SwitchSpec *sp;

    for (sp = specs; sp->type != SWITCH_END; sp++) {
        if ((sp->flags & needFlags) == needFlags) {
            char *ptr;

            ptr = (char *)record + sp->offset;
            switch (sp->type) {
            case SWITCH_STRING:
            case SWITCH_LIST:
                if (*((char **) ptr) != NULL) {
                    free(*((char **) ptr));
                    *((char **) ptr) = NULL;
                }
                break;

            case SWITCH_CUSTOM:
                assert(sp->customPtr != NULL);
                if ((*(char **)ptr != NULL) && 
                    (sp->customPtr->freeProc != NULL)) {
                    (*sp->customPtr->freeProc)((char *)record, sp->offset, 
                        sp->flags);
                }
                break;

            default:
                break;
            }
        }
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * SwitchModified --
 *
 *      Given the configuration specifications and one or more switch patterns
 *      (terminated by a NULL), indicate if any of the matching switches has
 *      been reset.
 *
 * Results:
 *      Returns 1 if one of the switches have changed, 0 otherwise.
 *
 *---------------------------------------------------------------------------
 */
int 
SwitchChanged TCL_VARARGS_DEF(SwitchSpec *, arg1)
{
    va_list argList;
    SwitchSpec *specs;
    SwitchSpec *sp;
    char *switchName;

    specs = TCL_VARARGS_START(SwitchSpec *, arg1, argList);
    while ((switchName = va_arg(argList, char *)) != NULL) {
        for (sp = specs; sp->type != SWITCH_END; sp++) {
            if ((Tcl_StringMatch(sp->switchName, switchName)) &&
                (sp->flags & SWITCH_SPECIFIED)) {
                va_end(argList);
                return 1;
            }
        }
    }
    va_end(argList);
    return 0;
}

int 
ExprDoubleFromObj(Tcl_Interp *interp, Tcl_Obj *objPtr, double *valuePtr)
{
    /* First try to extract the value as a double precision number. */
    if (Tcl_GetDoubleFromObj((Tcl_Interp *)NULL, objPtr, valuePtr) == TCL_OK) {
        return TCL_OK;
    }
    /* Then try to parse it as an expression. */
    if (Tcl_ExprDouble(interp, Tcl_GetString(objPtr), valuePtr) == TCL_OK) {
        return TCL_OK;
    }
    return TCL_ERROR;
}

int 
ExprIntFromObj(
    Tcl_Interp *interp, 
    Tcl_Obj *objPtr, 
    int *valuePtr)
{
    long lvalue;

    /* First try to extract the value as a simple integer. */
    if (Tcl_GetIntFromObj((Tcl_Interp *)NULL, objPtr, valuePtr) == TCL_OK) {
        return TCL_OK;
    }
    /* Otherwise try to parse it as an expression. */
    if (Tcl_ExprLong(interp, Tcl_GetString(objPtr), &lvalue) == TCL_OK) {
        *valuePtr = lvalue;
        return TCL_OK;
    }
    return TCL_ERROR;
}

}