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108 lines
2.3 KiB
C
108 lines
2.3 KiB
C
/* libguestfs - the guestfsd daemon
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* Copyright (C) 2009 Red Hat Inc.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include <config.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include "../src/guestfs_protocol.h"
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#include "daemon.h"
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#include "actions.h"
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static char **
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headtail (const char *prog, const char *flag, const char *n, char *path)
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{
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char *buf;
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char *out, *err;
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int r, len;
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char **lines;
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NEED_ROOT (NULL);
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ABS_PATH (path, NULL);
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/* Make the path relative to /sysroot. */
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len = strlen (path) + 9;
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buf = malloc (len);
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if (!buf) {
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reply_with_perror ("malloc");
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return NULL;
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}
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snprintf (buf, len, "/sysroot%s", path);
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r = command (&out, &err, prog, flag, n, buf, NULL);
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free (buf);
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if (r == -1) {
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reply_with_error ("%s %s %s: %s", prog, flag, n, err);
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free (out);
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free (err);
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return NULL;
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}
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free (err);
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#if 0
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/* Split it at the first whitespace. */
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len = strcspn (out, " \t\n");
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out[len] = '\0';
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#endif
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lines = split_lines (out);
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free (out);
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if (lines == NULL) return NULL;
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return lines;
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}
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char **
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do_head (char *path)
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{
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return headtail ("head", "-n", "10", path);
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}
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char **
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do_tail (char *path)
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{
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return headtail ("tail", "-n", "10", path);
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}
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char **
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do_head_n (int n, char *path)
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{
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char nbuf[16];
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snprintf (nbuf, sizeof nbuf, "%d", n);
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return headtail ("head", "-n", nbuf, path);
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}
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char **
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do_tail_n (int n, char *path)
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{
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char nbuf[16];
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if (n >= 0)
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snprintf (nbuf, sizeof nbuf, "%d", n);
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else
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snprintf (nbuf, sizeof nbuf, "+%d", -n);
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return headtail ("tail", "-n", nbuf, path);
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}
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