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[/] [or1k/] [trunk/] [insight/] [tcl/] [generic/] [tclBinary.c] - Blame information for rev 1774

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/*
 * tclBinary.c --
 *
 *      This file contains the implementation of the "binary" Tcl built-in
 *      command .
 *
 * Copyright (c) 1997 by Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclBinary.c,v 1.1.1.1 2002-01-16 10:25:25 markom Exp $
 */
 
#include <math.h>
#include "tclInt.h"
#include "tclPort.h"
 
/*
 * The following constants are used by GetFormatSpec to indicate various
 * special conditions in the parsing of a format specifier.
 */
 
#define BINARY_ALL -1           /* Use all elements in the argument. */
#define BINARY_NOCOUNT -2       /* No count was specified in format. */
 
/*
 * Prototypes for local procedures defined in this file:
 */
 
static int              GetFormatSpec _ANSI_ARGS_((char **formatPtr,
                            char *cmdPtr, int *countPtr));
static int              FormatNumber _ANSI_ARGS_((Tcl_Interp *interp, int type,
                            Tcl_Obj *src, char **cursorPtr));
static Tcl_Obj *        ScanNumber _ANSI_ARGS_((char *buffer, int type));
 
/*
 *----------------------------------------------------------------------
 *
 * Tcl_BinaryObjCmd --
 *
 *      This procedure implements the "binary" Tcl command.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */
 
int
Tcl_BinaryObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    int arg;                    /* Index of next argument to consume. */
    int value = 0;               /* Current integer value to be packed.
                                 * Initialized to avoid compiler warning. */
    char cmd;                   /* Current format character. */
    int count;                  /* Count associated with current format
                                 * character. */
    char *format;               /* Pointer to current position in format
                                 * string. */
    char *cursor;               /* Current position within result buffer. */
    char *maxPos;               /* Greatest position within result buffer that
                                 * cursor has visited.*/
    char *buffer;               /* Start of data buffer. */
    char *errorString, *errorValue, *str;
    int offset, size, length;
    Tcl_Obj *resultPtr;
 
    static char *subCmds[] = { "format", "scan", (char *) NULL };
    enum { BinaryFormat, BinaryScan } index;
 
    if (objc < 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "option ?arg arg ...?");
        return TCL_ERROR;
    }
 
    if (Tcl_GetIndexFromObj(interp, objv[1], subCmds, "option", 0,
            (int *) &index) != TCL_OK) {
        return TCL_ERROR;
    }
 
    switch (index) {
        case BinaryFormat:
            if (objc < 3) {
                Tcl_WrongNumArgs(interp, 2, objv, "formatString ?arg arg ...?");
                return TCL_ERROR;
            }
            /*
             * To avoid copying the data, we format the string in two passes.
             * The first pass computes the size of the output buffer.  The
             * second pass places the formatted data into the buffer.
             */
 
            format = Tcl_GetStringFromObj(objv[2], NULL);
            arg = 3;
            offset = length = 0;
            while (*format != 0) {
                if (!GetFormatSpec(&format, &cmd, &count)) {
                    break;
                }
                switch (cmd) {
                    case 'a':
                    case 'A':
                    case 'b':
                    case 'B':
                    case 'h':
                    case 'H':
                        /*
                         * For string-type specifiers, the count corresponds
                         * to the number of characters in a single argument.
                         */
 
                        if (arg >= objc) {
                            goto badIndex;
                        }
                        if (count == BINARY_ALL) {
                            (void)Tcl_GetStringFromObj(objv[arg], &count);
                        } else if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        arg++;
                        if (cmd == 'a' || cmd == 'A') {
                            offset += count;
                        } else if (cmd == 'b' || cmd == 'B') {
                            offset += (count + 7) / 8;
                        } else {
                            offset += (count + 1) / 2;
                        }
                        break;
 
                    case 'c':
                        size = 1;
                        goto doNumbers;
                    case 's':
                    case 'S':
                        size = 2;
                        goto doNumbers;
                    case 'i':
                    case 'I':
                        size = 4;
                        goto doNumbers;
                    case 'f':
                        size = sizeof(float);
                        goto doNumbers;
                    case 'd':
                        size = sizeof(double);
                    doNumbers:
                        if (arg >= objc) {
                            goto badIndex;
                        }
 
                        /*
                         * For number-type specifiers, the count corresponds
                         * to the number of elements in the list stored in
                         * a single argument.  If no count is specified, then
                         * the argument is taken as a single non-list value.
                         */
 
                        if (count == BINARY_NOCOUNT) {
                            arg++;
                            count = 1;
                        } else {
                            int listc;
                            Tcl_Obj **listv;
                            if (Tcl_ListObjGetElements(interp, objv[arg++],
                                    &listc, &listv) != TCL_OK) {
                                return TCL_ERROR;
                            }
                            if (count == BINARY_ALL) {
                                count = listc;
                            } else if (count > listc) {
                                errorString = "number of elements in list does not match count";
                                goto error;
                            }
                        }
                        offset += count*size;
                        break;
 
                    case 'x':
                        if (count == BINARY_ALL) {
                            errorString = "cannot use \"*\" in format string with \"x\"";
                            goto error;
                        } else if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        offset += count;
                        break;
                    case 'X':
                        if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        if ((count > offset) || (count == BINARY_ALL)) {
                            count = offset;
                        }
                        if (offset > length) {
                            length = offset;
                        }
                        offset -= count;
                        break;
                    case '@':
                        if (offset > length) {
                            length = offset;
                        }
                        if (count == BINARY_ALL) {
                            offset = length;
                        } else if (count == BINARY_NOCOUNT) {
                            goto badCount;
                        } else {
                            offset = count;
                        }
                        break;
                    default: {
                        char buf[2];
 
                        Tcl_ResetResult(interp);
                        buf[0] = cmd;
                        buf[1] = '\0';
                        Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
                                "bad field specifier \"", buf, "\"", NULL);
                        return TCL_ERROR;
                    }
                }
            }
            if (offset > length) {
                length = offset;
            }
            if (length == 0) {
                return TCL_OK;
            }
 
            /*
             * Prepare the result object by preallocating the caclulated
             * number of bytes and filling with nulls.
             */
 
            resultPtr = Tcl_GetObjResult(interp);
            Tcl_SetObjLength(resultPtr, length);
            buffer = Tcl_GetStringFromObj(resultPtr, NULL);
            memset(buffer, 0, (size_t) length);
 
            /*
             * Pack the data into the result object.  Note that we can skip
             * the error checking during this pass, since we have already
             * parsed the string once.
             */
 
            arg = 3;
            format = Tcl_GetStringFromObj(objv[2], NULL);
            cursor = buffer;
            maxPos = cursor;
            while (*format != 0) {
                if (!GetFormatSpec(&format, &cmd, &count)) {
                    break;
                }
                if ((count == 0) && (cmd != '@')) {
                    arg++;
                    continue;
                }
                switch (cmd) {
                    case 'a':
                    case 'A': {
                        char pad = (char) (cmd == 'a' ? '\0' : ' ');
 
                        str = Tcl_GetStringFromObj(objv[arg++], &length);
 
                        if (count == BINARY_ALL) {
                            count = length;
                        } else if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        if (length >= count) {
                            memcpy((VOID *) cursor, (VOID *) str,
                                    (size_t) count);
                        } else {
                            memcpy((VOID *) cursor, (VOID *) str,
                                    (size_t) length);
                            memset(cursor+length, pad,
                                    (size_t) (count - length));
                        }
                        cursor += count;
                        break;
                    }
                    case 'b':
                    case 'B': {
                        char *last;
 
                        str = Tcl_GetStringFromObj(objv[arg++], &length);
                        if (count == BINARY_ALL) {
                            count = length;
                        } else if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        last = cursor + ((count + 7) / 8);
                        if (count > length) {
                            count = length;
                        }
                        value = 0;
                        errorString = "binary";
                        if (cmd == 'B') {
                            for (offset = 0; offset < count; offset++) {
                                value <<= 1;
                                if (str[offset] == '1') {
                                    value |= 1;
                                } else if (str[offset] != '0') {
                                    errorValue = str;
                                    goto badValue;
                                }
                                if (((offset + 1) % 8) == 0) {
                                    *cursor++ = (char)(value & 0xff);
                                    value = 0;
                                }
                            }
                        } else {
                            for (offset = 0; offset < count; offset++) {
                                value >>= 1;
                                if (str[offset] == '1') {
                                    value |= 128;
                                } else if (str[offset] != '0') {
                                    errorValue = str;
                                    goto badValue;
                                }
                                if (!((offset + 1) % 8)) {
                                    *cursor++ = (char)(value & 0xff);
                                    value = 0;
                                }
                            }
                        }
                        if ((offset % 8) != 0) {
                            if (cmd == 'B') {
                                value <<= 8 - (offset % 8);
                            } else {
                                value >>= 8 - (offset % 8);
                            }
                            *cursor++ = (char)(value & 0xff);
                        }
                        while (cursor < last) {
                            *cursor++ = '\0';
                        }
                        break;
                    }
                    case 'h':
                    case 'H': {
                        char *last;
                        int c;
 
                        str = Tcl_GetStringFromObj(objv[arg++], &length);
                        if (count == BINARY_ALL) {
                            count = length;
                        } else if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        last = cursor + ((count + 1) / 2);
                        if (count > length) {
                            count = length;
                        }
                        value = 0;
                        errorString = "hexadecimal";
                        if (cmd == 'H') {
                            for (offset = 0; offset < count; offset++) {
                                value <<= 4;
                                c = tolower(((unsigned char *) str)[offset]);
                                if ((c >= 'a') && (c <= 'f')) {
                                    value |= ((c - 'a' + 10) & 0xf);
                                } else if ((c >= '0') && (c <= '9')) {
                                    value |= (c - '0') & 0xf;
                                } else {
                                    errorValue = str;
                                    goto badValue;
                                }
                                if (offset % 2) {
                                    *cursor++ = (char) value;
                                    value = 0;
                                }
                            }
                        } else {
                            for (offset = 0; offset < count; offset++) {
                                value >>= 4;
                                c = tolower(((unsigned char *) str)[offset]);
                                if ((c >= 'a') && (c <= 'f')) {
                                    value |= ((c - 'a' + 10) << 4) & 0xf0;
                                } else if ((c >= '0') && (c <= '9')) {
                                    value |= ((c - '0') << 4) & 0xf0;
                                } else {
                                    errorValue = str;
                                    goto badValue;
                                }
                                if (offset % 2) {
                                    *cursor++ = (char)(value & 0xff);
                                    value = 0;
                                }
                            }
                        }
                        if (offset % 2) {
                            if (cmd == 'H') {
                                value <<= 4;
                            } else {
                                value >>= 4;
                            }
                            *cursor++ = (char) value;
                        }
 
                        while (cursor < last) {
                            *cursor++ = '\0';
                        }
                        break;
                    }
                    case 'c':
                    case 's':
                    case 'S':
                    case 'i':
                    case 'I':
                    case 'd':
                    case 'f': {
                        int listc, i;
                        Tcl_Obj **listv;
 
                        if (count == BINARY_NOCOUNT) {
                            /*
                             * Note that we are casting away the const-ness of
                             * objv, but this is safe since we aren't going to
                             * modify the array.
                             */
 
                            listv = (Tcl_Obj**)(objv + arg);
                            listc = 1;
                            count = 1;
                        } else {
                            Tcl_ListObjGetElements(interp, objv[arg],
                                    &listc, &listv);
                            if (count == BINARY_ALL) {
                                count = listc;
                            }
                        }
                        arg++;
                        for (i = 0; i < count; i++) {
                            if (FormatNumber(interp, cmd, listv[i], &cursor)
                                    != TCL_OK) {
                                return TCL_ERROR;
                            }
                        }
                        break;
                    }
                    case 'x':
                        if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        memset(cursor, 0, (size_t) count);
                        cursor += count;
                        break;
                    case 'X':
                        if (cursor > maxPos) {
                            maxPos = cursor;
                        }
                        if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        if ((count == BINARY_ALL)
                                || (count > (cursor - buffer))) {
                            cursor = buffer;
                        } else {
                            cursor -= count;
                        }
                        break;
                    case '@':
                        if (cursor > maxPos) {
                            maxPos = cursor;
                        }
                        if (count == BINARY_ALL) {
                            cursor = maxPos;
                        } else {
                            cursor = buffer + count;
                        }
                        break;
                }
            }
            break;
 
        case BinaryScan: {
            int i;
            Tcl_Obj *valuePtr, *elementPtr;
 
            if (objc < 4) {
                Tcl_WrongNumArgs(interp, 2, objv,
                        "value formatString ?varName varName ...?");
                return TCL_ERROR;
            }
            buffer = Tcl_GetStringFromObj(objv[2], &length);
            format = Tcl_GetStringFromObj(objv[3], NULL);
            cursor = buffer;
            arg = 4;
            offset = 0;
            while (*format != 0) {
                if (!GetFormatSpec(&format, &cmd, &count)) {
                    goto done;
                }
                switch (cmd) {
                    case 'a':
                    case 'A':
                        if (arg >= objc) {
                            goto badIndex;
                        }
                        if (count == BINARY_ALL) {
                            count = length - offset;
                        } else {
                            if (count == BINARY_NOCOUNT) {
                                count = 1;
                            }
                            if (count > (length - offset)) {
                                goto done;
                            }
                        }
 
                        str = buffer + offset;
                        size = count;
 
                        /*
                         * Trim trailing nulls and spaces, if necessary.
                         */
 
                        if (cmd == 'A') {
                            while (size > 0) {
                                if (str[size-1] != '\0' && str[size-1] != ' ') {
                                    break;
                                }
                                size--;
                            }
                        }
                        valuePtr = Tcl_NewStringObj(str, size);
                        resultPtr = Tcl_ObjSetVar2(interp, objv[arg++], NULL,
                                valuePtr,
                                TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1);
                        if (resultPtr == NULL) {
                            Tcl_DecrRefCount(valuePtr); /* unneeded */
                            return TCL_ERROR;
                        }
                        offset += count;
                        break;
                    case 'b':
                    case 'B': {
                        char *dest;
 
                        if (arg >= objc) {
                            goto badIndex;
                        }
                        if (count == BINARY_ALL) {
                            count = (length - offset)*8;
                        } else {
                            if (count == BINARY_NOCOUNT) {
                                count = 1;
                            }
                            if (count > (length - offset)*8) {
                                goto done;
                            }
                        }
                        str = buffer + offset;
                        valuePtr = Tcl_NewObj();
                        Tcl_SetObjLength(valuePtr, count);
                        dest = Tcl_GetStringFromObj(valuePtr, NULL);
 
                        if (cmd == 'b') {
                            for (i = 0; i < count; i++) {
                                if (i % 8) {
                                    value >>= 1;
                                } else {
                                    value = *str++;
                                }
                                *dest++ = (char) ((value & 1) ? '1' : '0');
                            }
                        } else {
                            for (i = 0; i < count; i++) {
                                if (i % 8) {
                                    value <<= 1;
                                } else {
                                    value = *str++;
                                }
                                *dest++ = (char) ((value & 0x80) ? '1' : '0');
                            }
                        }
 
                        resultPtr = Tcl_ObjSetVar2(interp, objv[arg++], NULL,
                                valuePtr,
                                TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1);
                        if (resultPtr == NULL) {
                            Tcl_DecrRefCount(valuePtr); /* unneeded */
                            return TCL_ERROR;
                        }
                        offset += (count + 7 ) / 8;
                        break;
                    }
                    case 'h':
                    case 'H': {
                        char *dest;
                        int i;
                        static char hexdigit[] = "0123456789abcdef";
 
                        if (arg >= objc) {
                            goto badIndex;
                        }
                        if (count == BINARY_ALL) {
                            count = (length - offset)*2;
                        } else {
                            if (count == BINARY_NOCOUNT) {
                                count = 1;
                            }
                            if (count > (length - offset)*2) {
                                goto done;
                            }
                        }
                        str = buffer + offset;
                        valuePtr = Tcl_NewObj();
                        Tcl_SetObjLength(valuePtr, count);
                        dest = Tcl_GetStringFromObj(valuePtr, NULL);
 
                        if (cmd == 'h') {
                            for (i = 0; i < count; i++) {
                                if (i % 2) {
                                    value >>= 4;
                                } else {
                                    value = *str++;
                                }
                                *dest++ = hexdigit[value & 0xf];
                            }
                        } else {
                            for (i = 0; i < count; i++) {
                                if (i % 2) {
                                    value <<= 4;
                                } else {
                                    value = *str++;
                                }
                                *dest++ = hexdigit[(value >> 4) & 0xf];
                            }
                        }
 
                        resultPtr = Tcl_ObjSetVar2(interp, objv[arg++], NULL,
                                valuePtr,
                                TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1);
                        if (resultPtr == NULL) {
                            Tcl_DecrRefCount(valuePtr); /* unneeded */
                            return TCL_ERROR;
                        }
                        offset += (count + 1) / 2;
                        break;
                    }
                    case 'c':
                        size = 1;
                        goto scanNumber;
                    case 's':
                    case 'S':
                        size = 2;
                        goto scanNumber;
                    case 'i':
                    case 'I':
                        size = 4;
                        goto scanNumber;
                    case 'f':
                        size = sizeof(float);
                        goto scanNumber;
                    case 'd':
                        size = sizeof(double);
                        /* fall through */
                    scanNumber:
                        if (arg >= objc) {
                            goto badIndex;
                        }
                        if (count == BINARY_NOCOUNT) {
                            if ((length - offset) < size) {
                                goto done;
                            }
                            valuePtr = ScanNumber(buffer+offset, cmd);
                            offset += size;
                        } else {
                            if (count == BINARY_ALL) {
                                count = (length - offset) / size;
                            }
                            if ((length - offset) < (count * size)) {
                                goto done;
                            }
                            valuePtr = Tcl_NewObj();
                            str = buffer+offset;
                            for (i = 0; i < count; i++) {
                                elementPtr = ScanNumber(str, cmd);
                                str += size;
                                Tcl_ListObjAppendElement(NULL, valuePtr,
                                        elementPtr);
                            }
                            offset += count*size;
                        }
 
                        resultPtr = Tcl_ObjSetVar2(interp, objv[arg++], NULL,
                                valuePtr,
                                TCL_LEAVE_ERR_MSG | TCL_PARSE_PART1);
                        if (resultPtr == NULL) {
                            Tcl_DecrRefCount(valuePtr); /* unneeded */
                            return TCL_ERROR;
                        }
                        break;
                    case 'x':
                        if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        if ((count == BINARY_ALL)
                                || (count > (length - offset))) {
                            offset = length;
                        } else {
                            offset += count;
                        }
                        break;
                    case 'X':
                        if (count == BINARY_NOCOUNT) {
                            count = 1;
                        }
                        if ((count == BINARY_ALL) || (count > offset)) {
                            offset = 0;
                        } else {
                            offset -= count;
                        }
                        break;
                    case '@':
                        if (count == BINARY_NOCOUNT) {
                            goto badCount;
                        }
                        if ((count == BINARY_ALL) || (count > length)) {
                            offset = length;
                        } else {
                            offset = count;
                        }
                        break;
                    default: {
                        char buf[2];
 
                        Tcl_ResetResult(interp);
                        buf[0] = cmd;
                        buf[1] = '\0';
                        Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
                                "bad field specifier \"", buf, "\"", NULL);
                        return TCL_ERROR;
                    }
                }
            }
 
            /*
             * Set the result to the last position of the cursor.
             */
 
            done:
            Tcl_ResetResult(interp);
            Tcl_SetLongObj(Tcl_GetObjResult(interp), arg - 4);
            break;
        }
    }
    return TCL_OK;
 
    badValue:
    Tcl_ResetResult(interp);
    Tcl_AppendStringsToObj(Tcl_GetObjResult(interp), "expected ", errorString,
            " string but got \"", errorValue, "\" instead", NULL);
    return TCL_ERROR;
 
    badCount:
    errorString = "missing count for \"@\" field specifier";
    goto error;
 
    badIndex:
    errorString = "not enough arguments for all format specifiers";
    goto error;
 
    error:
    Tcl_ResetResult(interp);
    Tcl_AppendToObj(Tcl_GetObjResult(interp), errorString, -1);
    return TCL_ERROR;
}
 
/*
 *----------------------------------------------------------------------
 *
 * GetFormatSpec --
 *
 *      This function parses the format strings used in the binary
 *      format and scan commands.
 *
 * Results:
 *      Moves the formatPtr to the start of the next command. Returns
 *      the current command character and count in cmdPtr and countPtr.
 *      The count is set to BINARY_ALL if the count character was '*'
 *      or BINARY_NOCOUNT if no count was specified.  Returns 1 on
 *      success, or 0 if the string did not have a format specifier.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
static int
GetFormatSpec(formatPtr, cmdPtr, countPtr)
    char **formatPtr;           /* Pointer to format string. */
    char *cmdPtr;               /* Pointer to location of command char. */
    int *countPtr;              /* Pointer to repeat count value. */
{
    /*
     * Skip any leading blanks.
     */
 
    while (**formatPtr == ' ') {
        (*formatPtr)++;
    }
 
    /*
     * The string was empty, except for whitespace, so fail.
     */
 
    if (!(**formatPtr)) {
        return 0;
    }
 
    /*
     * Extract the command character and any trailing digits or '*'.
     */
 
    *cmdPtr = **formatPtr;
    (*formatPtr)++;
    if (**formatPtr == '*') {
        (*formatPtr)++;
        (*countPtr) = BINARY_ALL;
    } else if (isdigit(UCHAR(**formatPtr))) {
        (*countPtr) = strtoul(*formatPtr, formatPtr, 10);
    } else {
        (*countPtr) = BINARY_NOCOUNT;
    }
    return 1;
}
 
/*
 *----------------------------------------------------------------------
 *
 * FormatNumber --
 *
 *      This routine is called by Tcl_BinaryObjCmd to format a number
 *      into a location pointed at by cursor.
 *
 * Results:
 *       A standard Tcl result.
 *
 * Side effects:
 *      Moves the cursor to the next location to be written into.
 *
 *----------------------------------------------------------------------
 */
 
static int
FormatNumber(interp, type, src, cursorPtr)
    Tcl_Interp *interp;         /* Current interpreter, used to report
                                 * errors. */
    int type;                   /* Type of number to format. */
    Tcl_Obj *src;               /* Number to format. */
    char **cursorPtr;           /* Pointer to index into destination buffer. */
{
    int value;
    double dvalue;
    char cmd = (char)type;
 
    if (cmd == 'd' || cmd == 'f') {
        /*
         * For floating point types, we need to copy the data using
         * memcpy to avoid alignment issues.
         */
 
        if (Tcl_GetDoubleFromObj(interp, src, &dvalue) != TCL_OK) {
            return TCL_ERROR;
        }
        if (cmd == 'd') {
            memcpy((*cursorPtr), &dvalue, sizeof(double));
            (*cursorPtr) += sizeof(double);
        } else {
            float fvalue;
 
            /*
             * Because some compilers will generate floating point exceptions
             * on an overflow cast (e.g. Borland), we restrict the values
             * to the valid range for float.
             */
 
            if (fabs(dvalue) > (double)FLT_MAX) {
                fvalue = (dvalue >= 0.0) ? FLT_MAX : -FLT_MAX;
            } else {
                fvalue = (float) dvalue;
            }
            memcpy((*cursorPtr), &fvalue, sizeof(float));
            (*cursorPtr) += sizeof(float);
        }
    } else {
        if (Tcl_GetIntFromObj(interp, src, &value) != TCL_OK) {
            return TCL_ERROR;
        }
        if (cmd == 'c') {
            *(*cursorPtr)++ = (char)(value & 0xff);
        } else if (cmd == 's') {
            *(*cursorPtr)++ = (char)(value & 0xff);
            *(*cursorPtr)++ = (char)((value >> 8) & 0xff);
        } else if (cmd == 'S') {
            *(*cursorPtr)++ = (char)((value >> 8) & 0xff);
            *(*cursorPtr)++ = (char)(value & 0xff);
        } else if (cmd == 'i') {
            *(*cursorPtr)++ = (char)(value & 0xff);
            *(*cursorPtr)++ = (char)((value >> 8) & 0xff);
            *(*cursorPtr)++ = (char)((value >> 16) & 0xff);
            *(*cursorPtr)++ = (char)((value >> 24) & 0xff);
        } else if (cmd == 'I') {
            *(*cursorPtr)++ = (char)((value >> 24) & 0xff);
            *(*cursorPtr)++ = (char)((value >> 16) & 0xff);
            *(*cursorPtr)++ = (char)((value >> 8) & 0xff);
            *(*cursorPtr)++ = (char)(value & 0xff);
        }
    }
    return TCL_OK;
}
 
/*
 *----------------------------------------------------------------------
 *
 * ScanNumber --
 *
 *      This routine is called by Tcl_BinaryObjCmd to scan a number
 *      out of a buffer.
 *
 * Results:
 *      Returns a newly created object containing the scanned number.
 *      This object has a ref count of zero.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */
 
static Tcl_Obj *
ScanNumber(buffer, type)
    char *buffer;               /* Buffer to scan number from. */
    int type;                   /* Format character from "binary scan" */
{
    int value;
 
    /*
     * We cannot rely on the compiler to properly sign extend integer values
     * when we cast from smaller values to larger values because we don't know
     * the exact size of the integer types.  So, we have to handle sign
     * extension explicitly by checking the high bit and padding with 1's as
     * needed.
     */
 
    switch ((char) type) {
        case 'c':
            value = buffer[0];
 
            if (value & 0x80) {
                value |= -0x100;
            }
            return Tcl_NewLongObj((long)value);
        case 's':
            value = (((unsigned char)buffer[0])
                    + ((unsigned char)buffer[1] << 8));
            goto shortValue;
        case 'S':
            value = (((unsigned char)buffer[1])
                    + ((unsigned char)buffer[0] << 8));
            shortValue:
            if (value & 0x8000) {
                value |= -0x10000;
            }
            return Tcl_NewLongObj((long)value);
        case 'i':
            value =  (((unsigned char)buffer[0])
                    + ((unsigned char)buffer[1] << 8)
                    + ((unsigned char)buffer[2] << 16)
                    + ((unsigned char)buffer[3] << 24));
            goto intValue;
        case 'I':
            value = (((unsigned char)buffer[3])
                    + ((unsigned char)buffer[2] << 8)
                    + ((unsigned char)buffer[1] << 16)
                    + ((unsigned char)buffer[0] << 24));
            intValue:
            /*
             * Check to see if the value was sign extended properly on
             * systems where an int is more than 32-bits.
             */
 
            if ((value & (((unsigned int)1)<<31)) && (value > 0)) {
                value -= (((unsigned int)1)<<31);
                value -= (((unsigned int)1)<<31);
            }
 
            return Tcl_NewLongObj((long)value);
        case 'f': {
            float fvalue;
            memcpy(&fvalue, buffer, sizeof(float));
            return Tcl_NewDoubleObj(fvalue);
        }
        case 'd': {
            double dvalue;
            memcpy(&dvalue, buffer, sizeof(double));
            return Tcl_NewDoubleObj(dvalue);
        }
    }
    return NULL;
}
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[/] [or1k/] [trunk/] [insight/] [tcl/] [generic/] [tclBinary.c] - Blame information for rev 1774

Line No.	Rev	Author	Line
1	578	markom	`/*`
2			`* tclBinary.c --`
3			`*`
4			`* This file contains the implementation of the "binary" Tcl built-in`
5			`* command .`
6			`*`
7			`* Copyright (c) 1997 by Sun Microsystems, Inc.`
8			`*`
9			`* See the file "license.terms" for information on usage and redistribution`
10			`* of this file, and for a DISCLAIMER OF ALL WARRANTIES.`
11			`*`
12			`* RCS: @(#) $Id: tclBinary.c,v 1.1.1.1 2002-01-16 10:25:25 markom Exp $`
13			`*/`
14
15			`#include <math.h>`
16			`#include "tclInt.h"`
17			`#include "tclPort.h"`
18
19			`/*`
20			`* The following constants are used by GetFormatSpec to indicate various`
21			`* special conditions in the parsing of a format specifier.`
22			`*/`
23
24			`#define BINARY_ALL -1 /* Use all elements in the argument. */`
25			`#define BINARY_NOCOUNT -2 /* No count was specified in format. */`
26
27			`/*`
28			`* Prototypes for local procedures defined in this file:`
29			`*/`
30
31			`static int GetFormatSpec _ANSI_ARGS_((char **formatPtr,`
32			`char cmdPtr, int countPtr));`
33			`static int FormatNumber _ANSI_ARGS_((Tcl_Interp *interp, int type,`
34			`Tcl_Obj src, char *cursorPtr));`
35			`static Tcl_Obj * ScanNumber _ANSI_ARGS_((char *buffer, int type));`
36
37			`/*`
38			`*----------------------------------------------------------------------`
39			`*`
40			`* Tcl_BinaryObjCmd --`