lineedit.c

完整的Bell实验室的嵌入式文件系统TFS

            curPos++;
        }
        if (curPos < eol) {
            new = curPos+1;
            strcpy(now,new);
            cnt = strlen(now);
            putbytes(now,cnt);
            curPos = now + cnt;
            while(curPos <= eol) {
                putchar(' ');
                curPos++;
                cnt++;
            }
            backup(cnt);
        }
        else {
            curPos = now;
            delete_to_end();
            return;
        }
        curPos = now;
        lineLen = strlen(startOfLine);
    }
}

static void
delete_to_end()
{
    char    *eol, *now, *sol;

    eol = startOfLine + lineLen;
    now = curPos;
    if (curPos == eol)
        return;
    while(curPos < eol) {
        putchar(' ');
        curPos++;
    }
    if (now == startOfLine)
        sol = now+1;
    else
        sol = now;
    while(curPos >= sol) {
        putchar('\b');
        curPos--;
    }
    lineLen = now - startOfLine;
    if (lineLen == 0) {
        curPos = startOfLine;
        *curPos = 0;
    }
    else
        *(curPos+1) = '\0';
}

static void
ldelete()
{
    char    *eol, *now;
    int cnt;

    if (lineLen == 0)
        return;
    cnt = 0;
    eol = startOfLine + lineLen - 1;
    now = curPos;
    if (curPos != eol) {
        while(curPos <= eol) {
            *curPos = *(curPos+1);
            curPos++;
            cnt++;
        }
        putbytes(now,cnt-1);
        putchar(' ');
        backup((int)cnt);
    }
    else {
        puts(" \b\b");
        *eol = '\0';
        now--;
    }
    curPos = now;
    lineLen--;
    if (lineLen == 0)
        curPos = startOfLine;
}

/* showdone():
 * Used as common completion code for the showprev() and
 * shownext() functions below.
 */
static void
showdone(int idx)
{
    if (idx == HMAX) {
        printf("History buffer empty.\007\n");
        lMode = NEITHER;
        return;
    }

    backup((int)(curPos - startOfLine));
    lineLen = strlen(cmdhistory[shwidx]);
    putbytes(cmdhistory[shwidx],lineLen);
    lerase((int)(lastsize-lineLen));
    backup((int)(lineLen));
    strcpy(startOfLine,cmdhistory[shwidx]);
    curPos = startOfLine;
    lastsize = lineLen;
}

/* showprev() & shownext():
 * Show previous or next command in history list based on 
 * the current position in the list being established by
 * the shwidx variable.
 */
static void
showprev()
{
    int i;

    if (shwidx == 0)
        shwidx = HMAX-1;
    else
        shwidx--;

    for(i=0;i<HMAX;i++) {
        if (*cmdhistory[shwidx])
            break;
        if (shwidx == 0)
            shwidx = HMAX-1;
        else
            shwidx--;
    }
    showdone(i);
}


static void
shownext()
{
    int i;

    if (shwidx == HMAX-1)
        shwidx = 0;
    else
        shwidx++;

    for(i=0;i<HMAX;i++) {
        if (*cmdhistory[shwidx])
            break;
        if (shwidx == HMAX)
            shwidx = 0;
        else
            shwidx++;
    }
    showdone(i);
}

static void
backup(count)
int count;
{
    char    string[MAXLINESIZE];
    int i;

    if (count <= 0)
        return;
    *string = '\0';
    for(i=0;i<count;i++)
        strcat(string,"\b");
    putbytes(string,count);
}

static void
lerase(int count)
{
    char    string[MAXLINESIZE];
    int i;

    if (count <= 0)
        return;
    *string = '\0';
    for(i=0;i<count;i++)
        strcat(string," ");
    for(i=0;i<count;i++)
        strcat(string,"\b");
    putbytes(string,count*2);
}

static void
gotoend()
{
    char    string[MAXLINESIZE], *eol;
    int i;

    eol = startOfLine + lineLen -1;
    for (i=0;i<MAXLINESIZE-1;i++) {
        if (curPos == eol)
            break;
        string[i] = *curPos++;
    }
    if (i)
        putbytes(string,i);
}

static void
gotobegin()
{
    char    string[MAXLINESIZE];
    int i;

    i = 0;
    while(curPos != startOfLine) {
        string[i++] = '\b';
        curPos--;
    }
    putbytes(string,i);
}

/* History():
 * Command used at the CLI to allow the user to dump the content
 * of the history buffer.
 */
char * HistoryHelp[] = {
        "Display command history",
        "",
        0,
};
    
int
History(int argc,char *argv[])
{
    int i;

    for(i=stridx;i<HMAX;i++) {
        if (cmdhistory[i][0])
            printf("%s\n",cmdhistory[i]);
    }
    if (stridx) {
        for(i=0;i<stridx;i++) {
            if (cmdhistory[i][0])
                printf("%s\n",cmdhistory[i]);
        }
    }
    return(CMD_SUCCESS);
}

/* historyinit():
 * Initialize the command history...
 */
void
historyinit()
{
    int i;

    shwidx = stridx = 0;
    for (i=0;i<HMAX;i++)
        cmdhistory[i][0] = 0;
}

/* historylog():
 * This function is called by the CLI retrieval code to store away
 * the command in the CLI history list, a circular queue
 * (size HMAX) of most recent commands.
 */
void
historylog(char *cmdline)
{
    int idx;

    if (strlen(cmdline) >= HISTLINESIZE)
        return;

    if (stridx == 0)
        idx = HMAX-1;
    else
        idx = stridx -1;

    /* don't store if this command is same as last command */
    if (strcmp(cmdhistory[idx],cmdline) == 0)
        return;

    if (stridx == HMAX)
        stridx = 0;

    strcpy(cmdhistory[stridx++],cmdline);
}


static void
historysearch(void)
{
    static char string[100];
    char    *s, *ptr, *last, C;
    int size, len, count;

    lerase((int)lastsize);
    s = string;
    size = 0;
    while(1) {
        C = getchar();
        if (C == '\b') {
            if (size == 0)
                continue;
            puts("\b \b");
            s--;
            size--;
            continue;
        }
        if ((C == '\r') || (C == '\n'))
            break;
        putchar(C);
        size++;
        *s++ = C;
    }
    backup((int)(size+1));
    if (size != 0)
        *s = '\0';
    else 
        size = strlen(string);

    count = 0;

    while(1) {
        ptr = cmdhistory[srchidx];
        len = strlen(ptr);
        last = ptr + len - size + 1;
        while(ptr < last) {
            if (strncmp(ptr,string,size) == 0) 
                goto gotmatch;
            ptr++;
        }
        if (srchidx == 0)
            srchidx = HMAX-1;
        else
            srchidx--;
        if (++count == HMAX) {
            backup((int)(curPos - startOfLine));
            lineLen = 0;
            lerase((int)(size+1));
            backup((int)(lineLen));
            *startOfLine = '\0';
            curPos = startOfLine;
            lastsize = lineLen;
            return;
        }
    }
gotmatch:
    backup((int)(curPos - startOfLine));
    lineLen = strlen(cmdhistory[srchidx]);
    putbytes(cmdhistory[srchidx],lineLen);
    lerase((int)(lastsize-lineLen));
    backup((int)(lineLen));
    strcpy(startOfLine,cmdhistory[srchidx]);
    curPos = startOfLine;
    lastsize = lineLen;
    if (srchidx == 0)
        srchidx = HMAX-1;
    else
        srchidx--;
    return;
}

#endif