DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (d1ed7de67f5a)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * ``thrashview'' is a program that reads a binary stream of addresses
 * from stdin and displays the pattern graphically in a window.
 */

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <unistd.h>
#include <X11/Xlib.h>
#include <fstream>
#include <getopt.h>

#define GET_DISPLAY_FD(display_) ConnectionNumber(display_)

static bool opt_working_set = false;
static bool opt_fixed = false;

static Display *display;
static Window window;
static GC gc;
static XColor colors[256];
const unsigned int cellsize = 4;
static unsigned int width = 64 * cellsize;
static unsigned int height = 64 * cellsize;

#define PAGESIZE 4096
#define MAXPAGES 4096  // should hold 16MB worth of code
static unsigned int minpage = static_cast<unsigned int>(-1);
static unsigned int maxpage = 0;
static unsigned char pages[MAXPAGES];


/**
 * Create a simple window and the X objects we'll need to talk with it.
 */
static int
init()
{
    display = XOpenDisplay(0);
    if (! display)
        return 0;

    window =
        XCreateSimpleWindow(display,
                            RootWindow(display, 0),
                            1, 1, width, height,
                            0,
                            BlackPixel(display, 0),
                            BlackPixel(display, 0));

    if (! window)
        return 0;

    gc = XCreateGC(display, window, 0, 0);
    if (! gc)
        return 0;

    // Set up a grayscale
    const unsigned int ncolors = sizeof colors / sizeof colors[0];
    const unsigned short step = 65536 / ncolors;
    unsigned short brightness = 0;

    XColor *color = colors;
    XColor *limit = colors + ncolors;
    for (; color < limit; ++color, brightness += step) {
        color->red   = brightness;
        color->green = brightness;
        color->blue  = brightness;
        XAllocColor(display, DefaultColormap(display, 0), color);
    }

    // We want exposes and resizes.
    XSelectInput(display, window, ExposureMask | StructureNotifyMask);

    XMapWindow(display, window);
    XFlush(display);

    return 1;
}

/**
 * Age pages that haven't been recently touched.
 */
static void
decay()
{
    int ws_immediate = 0, ws_longterm = 0;

    unsigned char *page = pages;
    unsigned char *limit = pages + (maxpage - minpage) + 1;
    for (; page < limit; ++page) {
        if (opt_working_set) {
            if (*page == 255)
                ++ws_immediate;
            if (*page)
                ++ws_longterm;
        }

        if (*page) {
            *page /= 8;
            *page *= 7;
        }
    }

    if (opt_working_set) {
        dec(cout);
        cout << "immediate: " << ws_immediate << " pages, ";
        cout << "longterm: " << ws_longterm << " pages, ";
        cout << "mapped: " << ((maxpage - minpage) + 1) << " pages";
        cout << endl;
    }
}

/**
 * Blast the state of our pages to the screen.
 */
static int
handle_expose(const XExposeEvent& event)
{
    //printf("handle_expose(%d, %d, %d, %d)\n", event.x, event.y, event.width, event.height);

    int i = event.x / cellsize;
    int imost = i + event.width / cellsize + 1;

    int j = event.y / cellsize;
    int jmost = j + event.height / cellsize + 1;

    unsigned char *last_cell = pages + maxpage - minpage;
    unsigned char *row = pages + j;
    for (int y = j * cellsize, ymost = jmost * cellsize;
         y < ymost;
         y += cellsize, row += width / cellsize) {
        unsigned char *cell = row + i;
        for (int x = i * cellsize, xmost = imost * cellsize;
             x < xmost;
             x += cellsize, ++cell) {
            unsigned int pixel = (cell <= last_cell) ? colors[*cell].pixel : colors[0].pixel;
            XSetForeground(display, gc, pixel);
            XFillRectangle(display, window, gc, x, y, cellsize - 1, cellsize - 1);
        }
    }

    XFlush(display);

    return 1;
}

/**
 * Invalidate the entire window.
 */
static void
invalidate_window()
{
    XExposeEvent event;
    event.x = event.y = 0;
    event.width = width;
    event.height = height;

    handle_expose(event);
}

/**
 * Handle a configure event.
 */
static int
handle_configure(const XConfigureEvent& event)
{
    //printf("handle_resize(%d, %d)\n", event.width, event.height);
    width = event.width - event.width % cellsize;
    height = event.height;
    return 1;
}

/**
 * Filter to select any message.
 */
static Bool
any_event(Display *display, XEvent *event, XPointer arg)
{
    return 1;
}

/**
 * An X event occurred. Process it and flush the queue.
 */
static int
handle_xevents()
{
    int ok;
    
    XEvent event;
    XNextEvent(display, &event);
    do {
        switch (event.type) {
        case Expose:
            ok = handle_expose(reinterpret_cast<const XExposeEvent&>(event));
            break;

        case ConfigureNotify:
            ok = handle_configure(reinterpret_cast<const XConfigureEvent&>(event));
            break;

        default:
            ok = 1;
        }
    } while (ok && XCheckIfEvent(display, &event, any_event, 0));

    return ok;
}

/**
 * Read address data from stdin.
 */
static int
read_addrs()
{
    unsigned int buf[1024];
    ssize_t count;
    while ((count = read(0, buf, sizeof buf)) > 0) {
        if (count % sizeof(unsigned int))
            cerr << "truncating unaligned read" << endl;

        count /= sizeof buf[0];

        unsigned int *addr = reinterpret_cast<unsigned int *>(buf);
        unsigned int *limit = addr + count;

        for (; addr < limit; ++addr) {
            // map the address to a page
            unsigned int page = *addr / PAGESIZE;

            // XXX Don't let stray addresses bring us down. Should
            // really fix this by knowing what the ranges of addresses
            // we ought to expect are (e.g., by reading the symtab)
            if (maxpage && page > maxpage && page - maxpage > MAXPAGES)
                continue;

            if (! opt_fixed) {
                // Potentially adjust minpage and maxpage to
                // accomodate an out-of-bounds address.
                if (page < minpage) {
                    if (maxpage) {
                        // everything needs to shift.
                        unsigned int shift = minpage - page;
                        memmove(pages + shift, pages, maxpage - minpage);
                        memset(pages, 0, shift);
                    }
                    minpage = page;
                }

                if (page > maxpage)
                    maxpage = page;
            }

            page -= minpage;
            pages[page] = 255;
        }
    }

    if (count < 0 && errno != EWOULDBLOCK) {
        perror("read");
        return 0;
    }

    return 1;
}

/**
 * Run the program
 */
static void
run()
{
    // We want non-blocking I/O on stdin so we can select on it.
    fcntl(STDIN_FILENO, F_SETFL, O_NONBLOCK);

    // The last time we refreshed the window.
    struct timeval last;
    gettimeofday(&last, 0);

    int ok;

    do {
        // Select on stdin and the connection to the X server.
        fd_set fds;
        FD_ZERO(&fds);
        FD_SET(STDIN_FILENO, &fds);
        FD_SET(GET_DISPLAY_FD(display), &fds);

        struct timeval tv;
        tv.tv_sec  = 1;
        tv.tv_usec = 0;

        ok = select(GET_DISPLAY_FD(display) + 1, &fds, 0, 0, &tv);
        if (ok < 0)
            break;

        if (maxpage) {
            // See if we've waited long enough to refresh the window.
            struct timeval now;
            gettimeofday(&now, 0);

            if (now.tv_sec != last.tv_sec) {
                // At least a second has gone by. Decay and refresh.
                last = now;
                decay();
                invalidate_window();
            }
            else if (now.tv_usec - last.tv_usec > 100000) {
                // At least 100msec have gone by. Refresh.
                last.tv_usec = now.tv_usec;
                invalidate_window();
            }
        }

        // Now check for X events and input.
        ok = 1;

        if (FD_ISSET(GET_DISPLAY_FD(display), &fds))
            ok = handle_xevents();

        if (FD_ISSET(STDIN_FILENO, &fds))
            ok = read_addrs();
    } while (ok);
}

/**
 * Tear down our window and stuff.
 */
static void
finish()
{
    if (window) {
        XUnmapWindow(display, window);
        XDestroyWindow(display, window);
    }

    if (display)
        XCloseDisplay(display);
}

static struct option opts[] = {
    { "working-set", no_argument,       0, 'w' },
    { "min",         required_argument, 0, 'm' },
    { "size",        required_argument, 0, 's' },
    { "max",         required_argument, 0, 'x' },
    { 0,             0,                 0, 0   }
};

static void
usage()
{
    cerr << "thrashview [--working-set] [--min=<min>] [--max=<max>] [--size=<size>]" << endl;
}

/**
 * Program starts here.
 */
int
main(int argc, char *argv[])
{
    int size = 0;

    while (1) {
        int option_index = 0;
        int c = getopt_long(argc, argv, "wm:x:s:", opts, &option_index);

        if (c < 0)
            break;

        switch (c) {
        case 'w':
            opt_working_set = true;
            break;

        case 'm':
            minpage = strtol(optarg, 0, 0) / PAGESIZE;
            opt_fixed = true;
            break;

        case 's':
            size = strtol(optarg, 0, 0) / PAGESIZE;
            break;

        case 'x':
            maxpage = strtol(optarg, 0, 0) / PAGESIZE;
            opt_fixed = true;
            break;

        default:
            usage();
            return 1;
        }
    }

    if (minpage && !maxpage) {
        if (!size) {
            cerr << argv[0] << ": minpage specified without maxpage or size" << endl;
            return 1;
        }

        maxpage = minpage + size;
    }

    if (opt_fixed && minpage > maxpage) {
        cerr << argv[0] << ": invalid page range" << endl;
        return 1;
    }

    if (init())
        run();

    finish();

    return 0;
}