root-tail/root-tail.c

/*
 * Copyright 2001 by Marco d'Itri <md@linux.it>
 *
 * Original version by Mike Baker, then maintained by pcg@goof.com.
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 */

#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <signal.h>
#include <time.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/types.h>
#if HAS_REGEX
#include <regex.h>
#endif
#include <X11/Xlib.h>
#include <X11/Xutil.h>

/* data structures */
struct logfile_entry {
    char *fname;                /* name of file                         */
    char *desc;                 /* alternative description              */
    FILE *fp;                   /* FILE struct associated with file     */
    ino_t inode;                /* inode of the file opened             */
    off_t last_size;            /* file size at the last check          */
    unsigned long color;        /* color to be used for printing        */
    struct logfile_entry *next;
};

struct linematrix {
    char *line;
    unsigned long color;
};


/* global variables */
unsigned int width = STD_WIDTH, listlen = STD_HEIGHT;
int win_x = LOC_X, win_y = LOC_Y;
int w = -1, h = -1, font_width, font_height, font_descent;
int do_reopen;
struct timeval interval = { 2, 400000 };        /* see Knuth */

/* command line options */
int opt_noinitial, opt_shade, opt_frame, opt_reverse, opt_nofilename,
    geom_mask, reload = 3600;
const char *command = NULL,
    *fontname = USE_FONT, *dispname = NULL, *def_color = DEF_COLOR;

struct logfile_entry *loglist = NULL, *loglist_tail = NULL;

Display *disp;
Window root;
GC WinGC;

#if HAS_REGEX
struct re_list {
    regex_t from;
    const char *to;
    struct re_list *next;
};
struct re_list *re_head, *re_tail;
#endif


/* prototypes */
void list_files(int);
void force_reopen(int);
void force_refresh(int);
void blank_window(int);

void InitWindow(void);
unsigned long GetColor(const char *);
void redraw(void);
void refresh(struct linematrix *, int, int);

void transform_line(char *s);
int lineinput(char *, int, FILE *);
void reopen(void);
void check_open_files(void);
FILE *openlog(struct logfile_entry *);
void main_loop(void);

void display_version(void);
void display_help(char *);
void install_signal(int, void (*)(int));
void *xstrdup(const char *);
void *xmalloc(size_t);
int daemonize(void);

/* signal handlers */
void list_files(int dummy)
{
    struct logfile_entry *e;

    fprintf(stderr, "Files opened:\n");
    for (e = loglist; e; e = e->next)
        fprintf(stderr, "\t%s (%s)\n", e->fname, e->desc);
}

void force_reopen(int dummy)
{
    do_reopen = 1;
}

void force_refresh(int dummy)
{
    XClearWindow(disp, root);
    redraw();
}

void blank_window(int dummy)
{
    XClearWindow(disp, root);
    XFlush(disp);
    exit(0);
}

/* X related functions */
unsigned long GetColor(const char *ColorName)
{
    XColor Color;
    XWindowAttributes Attributes;

    XGetWindowAttributes(disp, root, &Attributes);
    Color.pixel = 0;
    if (!XParseColor(disp, Attributes.colormap, ColorName, &Color))
        fprintf(stderr, "can't parse %s\n", ColorName);
    else if (!XAllocColor(disp, Attributes.colormap, &Color))
        fprintf(stderr, "can't allocate %s\n", ColorName);
    return Color.pixel;
}

void InitWindow(void)
{
    XGCValues gcv;
    Font font;
    unsigned long gcm;
    XFontStruct *info;
    int screen, ScreenWidth, ScreenHeight;

    if (!(disp = XOpenDisplay(dispname))) {
        fprintf(stderr, "Can't open display %s.\n", dispname);
        exit(1);
    }
    screen = DefaultScreen(disp);
    ScreenHeight = DisplayHeight(disp, screen);
    ScreenWidth = DisplayWidth(disp, screen);
    root = RootWindow(disp, screen);
    gcm = GCBackground;
    gcv.graphics_exposures = True;
    WinGC = XCreateGC(disp, root, gcm, &gcv);
    XMapWindow(disp, root);
    XSetForeground(disp, WinGC, GetColor(DEF_COLOR));

    font = XLoadFont(disp, fontname);
    XSetFont(disp, WinGC, font);
    info = XQueryFont(disp, font);
    font_width = info->max_bounds.width;
    font_descent = info->max_bounds.descent;
    font_height = info->max_bounds.ascent + font_descent;

    w = width * font_width;
    h = listlen * font_height;
    if (geom_mask & XNegative)
        win_x = win_x + ScreenWidth - w;
    if (geom_mask & YNegative)
        win_y = win_y + ScreenHeight - h;

    XSelectInput(disp, root, ExposureMask|FocusChangeMask);
}

/*
 * redraw does a complete redraw, rather than an update (i.e. the area
 * gets cleared first)
 * the rest is handled by regular refresh()'es
 */
void redraw(void)
{
    XClearArea(disp, root, win_x, win_y, w, h + font_descent + 2, True);
}

/* Just redraw everything without clearing (i.e. after an EXPOSE event) */
void refresh(struct linematrix *lines, int miny, int maxy)
{
    int lin;
    int offset = (listlen + 1) * font_height;
    unsigned long black_color = GetColor("black");

    miny -= win_y + font_height;
    maxy -= win_y - font_height;

    for (lin = listlen; lin--;) {
        int line;

        offset -= font_height;
        if (offset < miny || offset > maxy)
            continue;

        if (opt_reverse)
            line = listlen - lin - 1;
        else
            line = lin;

        if (opt_shade) {
            XSetForeground(disp, WinGC, black_color);
            XDrawString(disp, root, WinGC, win_x + 2, win_y + offset + 2,
                        lines[line].line, strlen(lines[line].line));
        }
        XSetForeground(disp, WinGC, lines[line].color);
        XDrawString(disp, root, WinGC, win_x, win_y + offset,
                    lines[line].line, strlen(lines[line].line));
    }

    if (opt_frame) {
        int bot_y = win_y + h + font_descent + 2;

        XDrawLine(disp, root, WinGC, win_x, win_y, win_x + w, win_y);
        XDrawLine(disp, root, WinGC, win_x + w, win_y, win_x + w, bot_y);
        XDrawLine(disp, root, WinGC, win_x + w, bot_y, win_x, bot_y);
        XDrawLine(disp, root, WinGC, win_x, bot_y, win_x, win_y);
    }
}

#if HAS_REGEX
void transform_line(char *s)
{
#ifdef I_AM_Md
    int i;
    if (1) {
        for (i = 16; s[i]; i++)
            s[i] = s[i + 11];
    }
    s[i + 1] = '\0';
#endif

    if (transformre) {
        int i;
        regmatch_t matched[16];

        i = regexec(&transformre, string, 16, matched, 0);
        if (i == 0) {                   /* matched */
        }
    }
}
#endif


/*
 * This routine should read 'width' characters and not more. However,
 * we really want to read width + 1 charachters if the last char is a '\n',
 * which we should remove afterwards. So, read width+1 chars and ungetc
 * the last character if it's not a newline. This means 'string' must be
 * width + 2 wide!
 */
int lineinput(char *string, int slen, FILE *f)
{
    int len;

    do {
        if (fgets(string, slen, f) == NULL)     /* EOF or Error */
            return 0;

        len = strlen(string);
    } while (len == 0);

    if (string[len - 1] == '\n')
        string[len - 1] = '\0';                 /* erase newline */
    else if (len >= slen - 1) {
        ungetc(string[len - 1], f);
        string[len - 1] = '\0';
    }

#if HAS_REGEX
    transform_line(string);
#endif
    return len;
}

/* input: reads file->fname
 * output: fills file->fp, file->inode
 * returns file->fp
 * in case of error, file->fp is NULL
 */
FILE *openlog(struct logfile_entry *file)
{
    struct stat stats;

    if ((file->fp = fopen(file->fname, "r")) == NULL) {
        file->fp = NULL;
        return NULL;
    }

    fstat(fileno(file->fp), &stats);
    if (S_ISFIFO(stats.st_mode)) {
        if (fcntl(fileno(file->fp), F_SETFL, O_NONBLOCK) < 0)
            perror("fcntl"), exit(1);
        file->inode = 0;
    } else
        file->inode = stats.st_ino;

    if (stats.st_size > (listlen + 1) * width) {
        char dummy[255];

        fseek(file->fp, -((listlen + 2) * width), SEEK_END);
        /* the pointer might point halfway some line. Let's
           be nice and skip this damaged line */
        lineinput(dummy, sizeof(dummy), file->fp);
    }

    file->last_size = stats.st_size;
    return file->fp;
}

void reopen(void)
{
    struct logfile_entry *e;

    for (e = loglist; e; e = e->next) {
        if (!e->inode)
            continue;                   /* skip stdin */

        if (e->fp)
            fclose(e->fp);
        /* if fp is NULL we will try again later */
        openlog(e);
    }

    do_reopen = 0;
}

void check_open_files(void)
{
    struct logfile_entry *e;
    struct stat stats;

    for (e = loglist; e; e = e->next) {
        if (!e->inode)
            continue;                           /* skip stdin */

        if (stat(e->fname, &stats) < 0) {       /* file missing? */
            sleep(1);
            if (e->fp)
                fclose(e->fp);
            if (openlog(e) == NULL)
                break;
        }

        if (stats.st_ino != e->inode)   {       /* file renamed? */
            if (e->fp)
                fclose(e->fp);
            if (openlog(e) == NULL)
                break;
        }

        if (stats.st_size < e->last_size) {     /* file truncated? */
            fseek(e->fp, 0, SEEK_SET);
            e->last_size = stats.st_size;
        }
    }
}

#define SCROLL_UP(lines, listlen)                               \
{                                                               \
    int cur_line;                                               \
    for (cur_line = 0; cur_line < (listlen - 1); cur_line++) {  \
        strcpy(lines[cur_line].line, lines[cur_line + 1].line); \
        lines[cur_line].color = lines[cur_line + 1].color;      \
    }                                                           \
}

void main_loop(void)
{
    struct linematrix *lines = xmalloc(sizeof(struct linematrix) * listlen);
    int lin, miny, maxy, buflen;
    char *buf;
    time_t lastreload;
    Region region = XCreateRegion();
    XEvent xev;

    maxy = 0;
    miny = win_y + h;
    buflen = width + 2;
    buf = xmalloc(buflen);
    lastreload = time(NULL);

    /* Initialize linematrix */
    for (lin = 0; lin < listlen; lin++) {
        lines[lin].line = xmalloc(buflen);
        strcpy(lines[lin].line, "~");
        lines[lin].color = GetColor(def_color);
    }

    if (!opt_noinitial)
        while (lineinput(buf, buflen, loglist->fp) != 0) {
            SCROLL_UP(lines, listlen);
            /* print the next line */
            strcpy(lines[listlen - 1].line, buf);
        }

    for (;;) {
        int need_update = 0;
        struct logfile_entry *current;
        static struct logfile_entry *lastprinted = NULL;

        /* read logs */
        for (current = loglist; current; current = current->next) {
            if (!current->fp)
                continue;               /* skip missing files */

            clearerr(current->fp);

            while (lineinput(buf, buflen, current->fp) != 0) {
                /* print filename if any, and if last line was from
                   different file */
                if (!opt_nofilename &&
                        !(lastprinted && lastprinted == current) &&
                        current->desc[0]) {
                    SCROLL_UP(lines, listlen);
                    sprintf(lines[listlen - 1].line, "[%s]", current->desc);
                    lines[listlen - 1].color = current->color;
                }

                SCROLL_UP(lines, listlen);
                strcpy(lines[listlen - 1].line, buf);
                lines[listlen - 1].color = current->color;

                lastprinted = current;
                need_update = 1;
            }
        }

        if (need_update)
            redraw();
        else {
            XFlush(disp);
            if (!XPending(disp)) {
                fd_set fdr;
                struct timeval to = interval;

                FD_ZERO(&fdr);
                FD_SET(ConnectionNumber(disp), &fdr);
                select(ConnectionNumber(disp) + 1, &fdr, 0, 0, &to);
            }
        }

        check_open_files();

        if (do_reopen)
            reopen();

        /* we ignore possible errors due to window resizing &c */
        while (XPending(disp)) {
            XNextEvent(disp, &xev);
            switch (xev.type) {
            case Expose:
                {
                    XRectangle r;

                    r.x = xev.xexpose.x;
                    r.y = xev.xexpose.y;
                    r.width = xev.xexpose.width;
                    r.height = xev.xexpose.height;
                    XUnionRectWithRegion(&r, region, region);
                    if (miny > r.y)
                        miny = r.y;
                    if (maxy < r.y + r.height)
                        maxy = r.y + r.height;
                }
                break;
            default:
#ifdef DEBUGMODE
                fprintf(stderr, "PANIC! Unknown event %d\n", xev.type);
#endif
                break;
            }
        }

        /* reload if requested */
        if (reload && lastreload + reload < time(NULL)) {
            if (command)
                system(command);

            reopen();
            lastreload = time(NULL);
        }

        if (!XEmptyRegion(region)) {
            XSetRegion(disp, WinGC, region);
            refresh(lines, miny, maxy);
            XDestroyRegion(region);
            region = XCreateRegion();
            maxy = 0;
            miny = win_y + h;
        }
    }
}


int main(int argc, char *argv[])
{
    int i;
    int opt_daemonize = 0;
#if HAS_REGEX
    char *transform = NULL;
#endif

    /* window needs to be initialized before colorlookups can be done */
    /* just a dummy to get the color lookups right */
    geom_mask = NoValue;
    InitWindow();

    for (i = 1; i < argc; i++) {
        if (argv[i][0] == '-' && argv[i][1] != '\0' && argv[i][1] != ',') {
            if (!strcmp(argv[i], "--?") ||
                !strcmp(argv[i], "--help") || !strcmp(argv[i], "-h"))
                display_help(argv[0]);
            else if (!strcmp(argv[i], "-V"))
                display_version();
            else if (!strcmp(argv[i], "-g") || !strcmp(argv[i], "-geometry"))
                geom_mask = XParseGeometry(argv[++i],
                        &win_x, &win_y, &width, &listlen);
            else if (!strcmp(argv[i], "-display"))
                dispname = argv[++i];
            else if (!strcmp(argv[i], "-font") || !strcmp(argv[i], "-fn"))
                fontname = argv[++i];
#if HAS_REGEX
            else if (!strcmp(argv[i], "-t"))
                transform = argv[++i];
#endif
            else if (!strcmp(argv[i], "-fork") || !strcmp(argv[i], "-f"))
                opt_daemonize = 1;
            else if (!strcmp(argv[i], "-reload")) {
                reload = atoi(argv[++i]);
                command = argv[++i];
            }
            else if (!strcmp(argv[i], "-shade"))
                opt_shade = 1;
            else if (!strcmp(argv[i], "-frame"))
                opt_frame = 1;
            else if (!strcmp(argv[i], "-no-filename"))
                opt_nofilename = 1;
            else if (!strcmp(argv[i], "-reverse"))
                opt_reverse = 1;
            else if (!strcmp(argv[i], "-color"))
                def_color = argv[++i];
            else if (!strcmp(argv[i], "-noinitial"))
                opt_noinitial = 1;
            else if (!strcmp(argv[i], "-interval") || !strcmp(argv[i], "-i")) {
                double iv = atof(argv[++i]);

                interval.tv_sec = (int) iv;
                interval.tv_usec = (iv - interval.tv_sec) * 1e6;
            } else {
                fprintf(stderr, "Unknown option '%s'.\n"
                        "Try --help for more information.\n", argv[i]);
                exit(1);
            }
        } else {                /* it must be a filename */
            struct logfile_entry *e;
            const char *fname, *desc, *fcolor = def_color;
            char *p;

            /* this is not foolproof yet (',' in filenames are not allowed) */
            fname = desc = argv[i];
            if ((p = strchr(argv[i], ','))) {
                *p = '\0';
                fcolor = p + 1;

                if ((p = strchr(fcolor, ','))) {
                    *p = '\0';
                    desc = p + 1;
                }
            }

            e = xmalloc(sizeof(struct logfile_entry));
            if (argv[i][0] == '-' && argv[i][1] == '\0') {
                if ((e->fp = fdopen(0, "r")) == NULL)
                    perror("fdopen"), exit(1);
                if (fcntl(0, F_SETFL, O_NONBLOCK) < 0)
                    perror("fcntl"), exit(1);
                e->fname = NULL;
                e->inode = 0;
                e->desc = xstrdup("stdin");
            } else {
                int l;

                e->fname = xstrdup(fname);
                if (openlog(e) == NULL)
                    perror(fname), exit(1);

                l = strlen(desc);
                if (l > width - 2)              /* must account for [ ] */
                    l = width - 2;
                e->desc = xmalloc(l + 1);
                memcpy(e->desc, desc, l);
                *(e->desc + l) = '\0';
            }

            e->color = GetColor(fcolor);
            e->next = NULL;

            if (!loglist)
                loglist = e;
            if (loglist_tail)
                loglist_tail->next = e;
            loglist_tail = e;
        }
    }

    if (!loglist) {
        fprintf(stderr, "You did not specify any files to tail\n"
                "use %s --help for help\n", argv[0]);
        exit(1);
    }

#if HAS_REGEX
    if (transform) {
        int i;

        transformre = xmalloc(sizeof(transformre));
        i = regcomp(&transformre, transform, REG_EXTENDED);
        if (i != 0) {
            char buf[512];

            regerror(i, &transformre, buf, sizeof(buf));
            fprintf(stderr, "Cannot compile regular expression: %s\n", buf);
        }
    }
#endif

    InitWindow();

    install_signal(SIGINT, blank_window);
    install_signal(SIGQUIT, blank_window);
    install_signal(SIGTERM, blank_window);
    install_signal(SIGHUP, force_reopen);
    install_signal(SIGUSR1, list_files);
    install_signal(SIGUSR2, force_refresh);

    if (opt_daemonize)
        daemonize();

    main_loop();

    exit(1);                    /* to make gcc -Wall stop complaining */
}

void install_signal(int sig, void (*handler)(int))
{
    struct sigaction action;

    action.sa_handler = handler;
    sigemptyset(&action.sa_mask);
    action.sa_flags = SA_RESTART;
    if (sigaction(sig, &action, NULL) < 0)
        fprintf(stderr, "sigaction(%d): %s\n", sig, strerror(errno)), exit(1);
}

void *xstrdup(const char *string)
{
    void *p;

    while ((p = strdup(string)) == NULL) {
        fprintf(stderr, "Memory exausted.");
        sleep(10);
    }
    return p;
}

void *xmalloc(size_t size)
{
    void *p;

    while ((p = malloc(size)) == NULL) {
        fprintf(stderr, "Memory exausted.");
        sleep(10);
    }
    return p;
}

void display_help(char *myname)
{
    printf("Usage: %s [options] file1[,color[,desc]] "
           "[file2[,color[,desc]] ...]\n", myname);
    printf(" -g | -geometry geometry   -g WIDTHxHEIGHT+X+Y\n"
            " -color    color           use color $color as default\n"
            " -reload sec command       reload after $sec and run command\n"
            "                           by default -- 3 mins\n"
            " -font FONTSPEC            (-fn) font to use\n"
            " -f | -fork                fork into background\n"
            " -reverse                  print new lines at the top\n"
            " -shade                    add shading to font\n"
            " -noinitial                don't display the last file lines on\n"
            "                           startup\n"
            " -i | -interval seconds    interval between checks (fractional\n"
            "                           values o.k.). Default 3\n"
            " -V                        display version information and exit\n"
            "\n");
    printf("Example:\n%s -g 80x25+100+50 -font fixed /var/log/messages,green "
         "/var/log/secure,red,'ALERT'\n", myname);
    exit(0);
}

void display_version(void) {
    printf("root-tail version " VERSION "\n");
    exit(0);
}

int daemonize(void) {
    switch (fork()) {
    case -1:
        return -1;
    case 0:
        break;
    default:
        _exit(0);
    }

    if (setsid() == -1)
        return -1;

    return 0;
}

Revision:	1.1
Committed:	Sun Mar 10 00:17:30 2002 UTC (24 years, 6 months ago) by pcg
Content type:	text/plain
Branch:	MAIN
Log Message:	* empty log message *
#	User	Rev	Content
1	pcg	1.1	/*
2			* Copyright 2001 by Marco d'Itri <md@linux.it>
3			*
4			* Original version by Mike Baker, then maintained by pcg@goof.com.
5			*
6			* This program is free software; you can redistribute it and/or modify
7			* it under the terms of the GNU General Public License as published by
8			* the Free Software Foundation; either version 2 of the License, or
9			* (at your option) any later version.
10			*
11			* This program is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15			*
16			* You should have received a copy of the GNU General Public License
17			* along with this program; if not, write to the Free Software
18			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
19			*/
20
21			#include "config.h"
22			#include <stdlib.h>
23			#include <stdio.h>
24			#include <unistd.h>
25			#include <string.h>
26			#include <signal.h>
27			#include <time.h>
28			#include <fcntl.h>
29			#include <errno.h>
30			#include <sys/time.h>
31			#include <sys/stat.h>
32			#include <sys/types.h>
33			#if HAS_REGEX
34			#include <regex.h>
35			#endif
36			#include <X11/Xlib.h>
37			#include <X11/Xutil.h>
38
39			/* data structures */
40			struct logfile_entry {
41			char fname; / name of file */
42			char desc; / alternative description */
43			FILE fp; / FILE struct associated with file */
44			ino_t inode; /* inode of the file opened */
45			off_t last_size; /* file size at the last check */
46			unsigned long color; /* color to be used for printing */
47			struct logfile_entry *next;
48			};
49
50			struct linematrix {
51			char *line;
52			unsigned long color;
53			};
54
55
56			/* global variables */
57			unsigned int width = STD_WIDTH, listlen = STD_HEIGHT;
58			int win_x = LOC_X, win_y = LOC_Y;
59			int w = -1, h = -1, font_width, font_height, font_descent;
60			int do_reopen;
61			struct timeval interval = { 2, 400000 }; /* see Knuth */
62
63			/* command line options */
64			int opt_noinitial, opt_shade, opt_frame, opt_reverse, opt_nofilename,
65			geom_mask, reload = 3600;
66			const char *command = NULL,
67			fontname = USE_FONT, dispname = NULL, *def_color = DEF_COLOR;
68
69			struct logfile_entry loglist = NULL, loglist_tail = NULL;
70
71			Display *disp;
72			Window root;
73			GC WinGC;
74
75			#if HAS_REGEX
76			struct re_list {
77			regex_t from;
78			const char *to;
79			struct re_list *next;
80			};
81			struct re_list re_head, re_tail;
82			#endif
83
84
85			/* prototypes */
86			void list_files(int);
87			void force_reopen(int);
88			void force_refresh(int);
89			void blank_window(int);
90
91			void InitWindow(void);
92			unsigned long GetColor(const char *);
93			void redraw(void);
94			void refresh(struct linematrix *, int, int);
95
96			void transform_line(char *s);
97			int lineinput(char , int, FILE );
98			void reopen(void);
99			void check_open_files(void);
100			FILE openlog(struct logfile_entry );
101			void main_loop(void);
102
103			void display_version(void);
104			void display_help(char *);
105			void install_signal(int, void (*)(int));
106			void xstrdup(const char );
107			void *xmalloc(size_t);
108			int daemonize(void);
109
110			/* signal handlers */
111			void list_files(int dummy)
112			{
113			struct logfile_entry *e;
114
115			fprintf(stderr, "Files opened:\n");
116			for (e = loglist; e; e = e->next)
117			fprintf(stderr, "\t%s (%s)\n", e->fname, e->desc);
118			}
119
120			void force_reopen(int dummy)
121			{
122			do_reopen = 1;
123			}
124
125			void force_refresh(int dummy)
126			{
127			XClearWindow(disp, root);
128			redraw();
129			}
130
131			void blank_window(int dummy)
132			{
133			XClearWindow(disp, root);
134			XFlush(disp);
135			exit(0);
136			}
137
138			/* X related functions */
139			unsigned long GetColor(const char *ColorName)
140			{
141			XColor Color;
142			XWindowAttributes Attributes;
143
144			XGetWindowAttributes(disp, root, &Attributes);
145			Color.pixel = 0;
146			if (!XParseColor(disp, Attributes.colormap, ColorName, &Color))
147			fprintf(stderr, "can't parse %s\n", ColorName);
148			else if (!XAllocColor(disp, Attributes.colormap, &Color))
149			fprintf(stderr, "can't allocate %s\n", ColorName);
150			return Color.pixel;
151			}
152
153			void InitWindow(void)
154			{
155			XGCValues gcv;
156			Font font;
157			unsigned long gcm;
158			XFontStruct *info;
159			int screen, ScreenWidth, ScreenHeight;
160
161			if (!(disp = XOpenDisplay(dispname))) {
162			fprintf(stderr, "Can't open display %s.\n", dispname);
163			exit(1);
164			}
165			screen = DefaultScreen(disp);
166			ScreenHeight = DisplayHeight(disp, screen);
167			ScreenWidth = DisplayWidth(disp, screen);
168			root = RootWindow(disp, screen);
169			gcm = GCBackground;
170			gcv.graphics_exposures = True;
171			WinGC = XCreateGC(disp, root, gcm, &gcv);
172			XMapWindow(disp, root);
173			XSetForeground(disp, WinGC, GetColor(DEF_COLOR));
174
175			font = XLoadFont(disp, fontname);
176			XSetFont(disp, WinGC, font);
177			info = XQueryFont(disp, font);
178			font_width = info->max_bounds.width;
179			font_descent = info->max_bounds.descent;
180			font_height = info->max_bounds.ascent + font_descent;
181
182			w = width * font_width;
183			h = listlen * font_height;
184			if (geom_mask & XNegative)
185			win_x = win_x + ScreenWidth - w;
186			if (geom_mask & YNegative)
187			win_y = win_y + ScreenHeight - h;
188
189			XSelectInput(disp, root, ExposureMask\|FocusChangeMask);
190			}
191
192			/*
193			* redraw does a complete redraw, rather than an update (i.e. the area
194			* gets cleared first)
195			* the rest is handled by regular refresh()'es
196			*/
197			void redraw(void)
198			{
199			XClearArea(disp, root, win_x, win_y, w, h + font_descent + 2, True);
200			}
201
202			/* Just redraw everything without clearing (i.e. after an EXPOSE event) */
203			void refresh(struct linematrix *lines, int miny, int maxy)
204			{
205			int lin;
206			int offset = (listlen + 1) * font_height;
207			unsigned long black_color = GetColor("black");
208
209			miny -= win_y + font_height;
210			maxy -= win_y - font_height;
211
212			for (lin = listlen; lin--;) {
213			int line;
214
215			offset -= font_height;
216			if (offset < miny \|\| offset > maxy)
217			continue;
218
219			if (opt_reverse)
220			line = listlen - lin - 1;
221			else
222			line = lin;
223
224			if (opt_shade) {
225			XSetForeground(disp, WinGC, black_color);
226			XDrawString(disp, root, WinGC, win_x + 2, win_y + offset + 2,
227			lines[line].line, strlen(lines[line].line));
228			}
229			XSetForeground(disp, WinGC, lines[line].color);
230			XDrawString(disp, root, WinGC, win_x, win_y + offset,
231			lines[line].line, strlen(lines[line].line));
232			}
233
234			if (opt_frame) {
235			int bot_y = win_y + h + font_descent + 2;
236
237			XDrawLine(disp, root, WinGC, win_x, win_y, win_x + w, win_y);
238			XDrawLine(disp, root, WinGC, win_x + w, win_y, win_x + w, bot_y);
239			XDrawLine(disp, root, WinGC, win_x + w, bot_y, win_x, bot_y);
240			XDrawLine(disp, root, WinGC, win_x, bot_y, win_x, win_y);
241			}
242			}
243
244			#if HAS_REGEX
245			void transform_line(char *s)
246			{
247			#ifdef I_AM_Md
248			int i;
249			if (1) {
250			for (i = 16; s[i]; i++)
251			s[i] = s[i + 11];
252			}
253			s[i + 1] = '\0';
254			#endif
255
256			if (transformre) {
257			int i;
258			regmatch_t matched[16];
259
260			i = regexec(&transformre, string, 16, matched, 0);
261			if (i == 0) { /* matched */
262			}
263			}
264			}
265			#endif
266
267
268			/*
269			* This routine should read 'width' characters and not more. However,
270			* we really want to read width + 1 charachters if the last char is a '\n',
271			* which we should remove afterwards. So, read width+1 chars and ungetc
272			* the last character if it's not a newline. This means 'string' must be
273			* width + 2 wide!
274			*/
275			int lineinput(char string, int slen, FILE f)
276			{
277			int len;
278
279			do {
280			if (fgets(string, slen, f) == NULL) /* EOF or Error */
281			return 0;
282
283			len = strlen(string);
284			} while (len == 0);
285
286			if (string[len - 1] == '\n')
287			string[len - 1] = '\0'; /* erase newline */
288			else if (len >= slen - 1) {
289			ungetc(string[len - 1], f);
290			string[len - 1] = '\0';
291			}
292
293			#if HAS_REGEX
294			transform_line(string);
295			#endif
296			return len;
297			}
298
299			/* input: reads file->fname
300			* output: fills file->fp, file->inode
301			* returns file->fp
302			* in case of error, file->fp is NULL
303			*/
304			FILE openlog(struct logfile_entry file)
305			{
306			struct stat stats;
307
308			if ((file->fp = fopen(file->fname, "r")) == NULL) {
309			file->fp = NULL;
310			return NULL;
311			}
312
313			fstat(fileno(file->fp), &stats);
314			if (S_ISFIFO(stats.st_mode)) {
315			if (fcntl(fileno(file->fp), F_SETFL, O_NONBLOCK) < 0)
316			perror("fcntl"), exit(1);
317			file->inode = 0;
318			} else
319			file->inode = stats.st_ino;
320
321			if (stats.st_size > (listlen + 1) * width) {
322			char dummy[255];
323
324			fseek(file->fp, -((listlen + 2) * width), SEEK_END);
325			/* the pointer might point halfway some line. Let's
326			be nice and skip this damaged line */
327			lineinput(dummy, sizeof(dummy), file->fp);
328			}
329
330			file->last_size = stats.st_size;
331			return file->fp;
332			}
333
334			void reopen(void)
335			{
336			struct logfile_entry *e;
337
338			for (e = loglist; e; e = e->next) {
339			if (!e->inode)
340			continue; /* skip stdin */
341
342			if (e->fp)
343			fclose(e->fp);
344			/* if fp is NULL we will try again later */
345			openlog(e);
346			}
347
348			do_reopen = 0;
349			}
350
351			void check_open_files(void)
352			{
353			struct logfile_entry *e;
354			struct stat stats;
355
356			for (e = loglist; e; e = e->next) {
357			if (!e->inode)
358			continue; /* skip stdin */
359
360			if (stat(e->fname, &stats) < 0) { /* file missing? */
361			sleep(1);
362			if (e->fp)
363			fclose(e->fp);
364			if (openlog(e) == NULL)
365			break;
366			}
367
368			if (stats.st_ino != e->inode) { /* file renamed? */
369			if (e->fp)
370			fclose(e->fp);
371			if (openlog(e) == NULL)
372			break;
373			}
374
375			if (stats.st_size < e->last_size) { /* file truncated? */
376			fseek(e->fp, 0, SEEK_SET);
377			e->last_size = stats.st_size;
378			}
379			}
380			}
381
382			#define SCROLL_UP(lines, listlen) \
383			{ \
384			int cur_line; \
385			for (cur_line = 0; cur_line < (listlen - 1); cur_line++) { \
386			strcpy(lines[cur_line].line, lines[cur_line + 1].line); \
387			lines[cur_line].color = lines[cur_line + 1].color; \
388			} \
389			}
390
391			void main_loop(void)
392			{
393			struct linematrix lines = xmalloc(sizeof(struct linematrix) listlen);
394			int lin, miny, maxy, buflen;
395			char *buf;
396			time_t lastreload;
397			Region region = XCreateRegion();
398			XEvent xev;
399
400			maxy = 0;
401			miny = win_y + h;
402			buflen = width + 2;
403			buf = xmalloc(buflen);
404			lastreload = time(NULL);
405
406			/* Initialize linematrix */
407			for (lin = 0; lin < listlen; lin++) {
408			lines[lin].line = xmalloc(buflen);
409			strcpy(lines[lin].line, "~");
410			lines[lin].color = GetColor(def_color);
411			}
412
413			if (!opt_noinitial)
414			while (lineinput(buf, buflen, loglist->fp) != 0) {
415			SCROLL_UP(lines, listlen);
416			/* print the next line */
417			strcpy(lines[listlen - 1].line, buf);
418			}
419
420			for (;;) {
421			int need_update = 0;
422			struct logfile_entry *current;
423			static struct logfile_entry *lastprinted = NULL;
424
425			/* read logs */
426			for (current = loglist; current; current = current->next) {
427			if (!current->fp)
428			continue; /* skip missing files */
429
430			clearerr(current->fp);
431
432			while (lineinput(buf, buflen, current->fp) != 0) {
433			/* print filename if any, and if last line was from
434			different file */
435			if (!opt_nofilename &&
436			!(lastprinted && lastprinted == current) &&
437			current->desc[0]) {
438			SCROLL_UP(lines, listlen);
439			sprintf(lines[listlen - 1].line, "[%s]", current->desc);
440			lines[listlen - 1].color = current->color;
441			}
442
443			SCROLL_UP(lines, listlen);
444			strcpy(lines[listlen - 1].line, buf);
445			lines[listlen - 1].color = current->color;
446
447			lastprinted = current;
448			need_update = 1;
449			}
450			}
451
452			if (need_update)
453			redraw();
454			else {
455			XFlush(disp);
456			if (!XPending(disp)) {
457			fd_set fdr;
458			struct timeval to = interval;
459
460			FD_ZERO(&fdr);
461			FD_SET(ConnectionNumber(disp), &fdr);
462			select(ConnectionNumber(disp) + 1, &fdr, 0, 0, &to);
463			}
464			}
465
466			check_open_files();
467
468			if (do_reopen)
469			reopen();
470
471			/* we ignore possible errors due to window resizing &c */
472			while (XPending(disp)) {
473			XNextEvent(disp, &xev);
474			switch (xev.type) {
475			case Expose:
476			{
477			XRectangle r;
478
479			r.x = xev.xexpose.x;
480			r.y = xev.xexpose.y;
481			r.width = xev.xexpose.width;
482			r.height = xev.xexpose.height;
483			XUnionRectWithRegion(&r, region, region);
484			if (miny > r.y)
485			miny = r.y;
486			if (maxy < r.y + r.height)
487			maxy = r.y + r.height;
488			}
489			break;
490			default:
491			#ifdef DEBUGMODE
492			fprintf(stderr, "PANIC! Unknown event %d\n", xev.type);
493			#endif
494			break;
495			}
496			}
497
498			/* reload if requested */
499			if (reload && lastreload + reload < time(NULL)) {
500			if (command)
501			system(command);
502
503			reopen();
504			lastreload = time(NULL);
505			}
506
507			if (!XEmptyRegion(region)) {
508			XSetRegion(disp, WinGC, region);
509			refresh(lines, miny, maxy);
510			XDestroyRegion(region);
511			region = XCreateRegion();
512			maxy = 0;
513			miny = win_y + h;
514			}
515			}
516			}
517
518
519			int main(int argc, char *argv[])
520			{
521			int i;
522			int opt_daemonize = 0;
523			#if HAS_REGEX
524			char *transform = NULL;
525			#endif
526
527			/* window needs to be initialized before colorlookups can be done */
528			/* just a dummy to get the color lookups right */
529			geom_mask = NoValue;
530			InitWindow();
531
532			for (i = 1; i < argc; i++) {
533			if (argv[i][0] == '-' && argv[i][1] != '\0' && argv[i][1] != ',') {
534			if (!strcmp(argv[i], "--?") \|\|
535			!strcmp(argv[i], "--help") \|\| !strcmp(argv[i], "-h"))
536			display_help(argv[0]);
537			else if (!strcmp(argv[i], "-V"))
538			display_version();
539			else if (!strcmp(argv[i], "-g") \|\| !strcmp(argv[i], "-geometry"))
540			geom_mask = XParseGeometry(argv[++i],
541			&win_x, &win_y, &width, &listlen);
542			else if (!strcmp(argv[i], "-display"))
543			dispname = argv[++i];
544			else if (!strcmp(argv[i], "-font") \|\| !strcmp(argv[i], "-fn"))
545			fontname = argv[++i];
546			#if HAS_REGEX
547			else if (!strcmp(argv[i], "-t"))
548			transform = argv[++i];
549			#endif
550			else if (!strcmp(argv[i], "-fork") \|\| !strcmp(argv[i], "-f"))
551			opt_daemonize = 1;
552			else if (!strcmp(argv[i], "-reload")) {
553			reload = atoi(argv[++i]);
554			command = argv[++i];
555			}
556			else if (!strcmp(argv[i], "-shade"))
557			opt_shade = 1;
558			else if (!strcmp(argv[i], "-frame"))
559			opt_frame = 1;
560			else if (!strcmp(argv[i], "-no-filename"))
561			opt_nofilename = 1;
562			else if (!strcmp(argv[i], "-reverse"))
563			opt_reverse = 1;
564			else if (!strcmp(argv[i], "-color"))
565			def_color = argv[++i];
566			else if (!strcmp(argv[i], "-noinitial"))
567			opt_noinitial = 1;
568			else if (!strcmp(argv[i], "-interval") \|\| !strcmp(argv[i], "-i")) {
569			double iv = atof(argv[++i]);
570
571			interval.tv_sec = (int) iv;
572			interval.tv_usec = (iv - interval.tv_sec) * 1e6;
573			} else {
574			fprintf(stderr, "Unknown option '%s'.\n"
575			"Try --help for more information.\n", argv[i]);
576			exit(1);
577			}
578			} else { /* it must be a filename */
579			struct logfile_entry *e;
580			const char fname, desc, *fcolor = def_color;
581			char *p;
582
583			/* this is not foolproof yet (',' in filenames are not allowed) */
584			fname = desc = argv[i];
585			if ((p = strchr(argv[i], ','))) {
586			*p = '\0';
587			fcolor = p + 1;
588
589			if ((p = strchr(fcolor, ','))) {
590			*p = '\0';
591			desc = p + 1;
592			}
593			}
594
595			e = xmalloc(sizeof(struct logfile_entry));
596			if (argv[i][0] == '-' && argv[i][1] == '\0') {
597			if ((e->fp = fdopen(0, "r")) == NULL)
598			perror("fdopen"), exit(1);
599			if (fcntl(0, F_SETFL, O_NONBLOCK) < 0)
600			perror("fcntl"), exit(1);
601			e->fname = NULL;
602			e->inode = 0;
603			e->desc = xstrdup("stdin");
604			} else {
605			int l;
606
607			e->fname = xstrdup(fname);
608			if (openlog(e) == NULL)
609			perror(fname), exit(1);
610
611			l = strlen(desc);
612			if (l > width - 2) /* must account for [ ] */
613			l = width - 2;
614			e->desc = xmalloc(l + 1);
615			memcpy(e->desc, desc, l);
616			*(e->desc + l) = '\0';
617			}
618
619			e->color = GetColor(fcolor);
620			e->next = NULL;
621
622			if (!loglist)
623			loglist = e;
624			if (loglist_tail)
625			loglist_tail->next = e;
626			loglist_tail = e;
627			}
628			}
629
630			if (!loglist) {
631			fprintf(stderr, "You did not specify any files to tail\n"
632			"use %s --help for help\n", argv[0]);
633			exit(1);
634			}
635
636			#if HAS_REGEX
637			if (transform) {
638			int i;
639
640			transformre = xmalloc(sizeof(transformre));
641			i = regcomp(&transformre, transform, REG_EXTENDED);
642			if (i != 0) {
643			char buf[512];
644
645			regerror(i, &transformre, buf, sizeof(buf));
646			fprintf(stderr, "Cannot compile regular expression: %s\n", buf);
647			}
648			}
649			#endif
650
651			InitWindow();
652
653			install_signal(SIGINT, blank_window);
654			install_signal(SIGQUIT, blank_window);
655			install_signal(SIGTERM, blank_window);
656			install_signal(SIGHUP, force_reopen);
657			install_signal(SIGUSR1, list_files);
658			install_signal(SIGUSR2, force_refresh);
659
660			if (opt_daemonize)
661			daemonize();
662
663			main_loop();
664
665			exit(1); /* to make gcc -Wall stop complaining */
666			}
667
668			void install_signal(int sig, void (*handler)(int))
669			{
670			struct sigaction action;
671
672			action.sa_handler = handler;
673			sigemptyset(&action.sa_mask);
674			action.sa_flags = SA_RESTART;
675			if (sigaction(sig, &action, NULL) < 0)
676			fprintf(stderr, "sigaction(%d): %s\n", sig, strerror(errno)), exit(1);
677			}
678
679			void xstrdup(const char string)
680			{
681			void *p;
682
683			while ((p = strdup(string)) == NULL) {
684			fprintf(stderr, "Memory exausted.");
685			sleep(10);
686			}
687			return p;
688			}
689
690			void *xmalloc(size_t size)
691			{
692			void *p;
693
694			while ((p = malloc(size)) == NULL) {
695			fprintf(stderr, "Memory exausted.");
696			sleep(10);
697			}
698			return p;
699			}
700
701			void display_help(char *myname)
702			{
703			printf("Usage: %s [options] file1[,color[,desc]] "
704			"[file2[,color[,desc]] ...]\n", myname);
705			printf(" -g \| -geometry geometry -g WIDTHxHEIGHT+X+Y\n"
706			" -color color use color $color as default\n"
707			" -reload sec command reload after $sec and run command\n"
708			" by default -- 3 mins\n"
709			" -font FONTSPEC (-fn) font to use\n"
710			" -f \| -fork fork into background\n"
711			" -reverse print new lines at the top\n"
712			" -shade add shading to font\n"
713			" -noinitial don't display the last file lines on\n"
714			" startup\n"
715			" -i \| -interval seconds interval between checks (fractional\n"
716			" values o.k.). Default 3\n"
717			" -V display version information and exit\n"
718			"\n");
719			printf("Example:\n%s -g 80x25+100+50 -font fixed /var/log/messages,green "
720			"/var/log/secure,red,'ALERT'\n", myname);
721			exit(0);
722			}
723
724			void display_version(void) {
725			printf("root-tail version " VERSION "\n");
726			exit(0);
727			}
728
729			int daemonize(void) {
730			switch (fork()) {
731			case -1:
732			return -1;
733			case 0:
734			break;
735			default:
736			_exit(0);
737			}
738
739			if (setsid() == -1)
740			return -1;
741
742			return 0;
743			}
744