/* libguestfs - the guestfsd daemon
- * Copyright (C) 2009 Red Hat Inc.
+ * Copyright (C) 2009 Red Hat Inc.
*
* 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
#include <config.h>
-#define _GNU_SOURCE /* for futimens(2) */
-
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <sys/stat.h>
+#include "../src/guestfs_protocol.h"
#include "daemon.h"
#include "actions.h"
do_touch (const char *path)
{
int fd;
+ int r;
+
+ CHROOT_IN;
+ fd = open (path, O_WRONLY | O_CREAT | O_NOCTTY, 0666);
+ CHROOT_OUT;
- NEED_ROOT;
+ if (fd == -1) {
+ reply_with_perror ("open: %s", path);
+ return -1;
+ }
+
+#ifdef HAVE_FUTIMENS
+ r = futimens (fd, NULL);
+#else
+ r = futimes (fd, NULL);
+#endif
+ if (r == -1) {
+ reply_with_perror ("futimens: %s", path);
+ close (fd);
+ return -1;
+ }
- if (path[0] != '/') {
- reply_with_error ("touch: path must start with a / character");
+ if (close (fd) == -1) {
+ reply_with_perror ("close: %s", path);
return -1;
}
+ return 0;
+}
+
+char *
+do_cat (const char *path)
+{
+ int fd;
+ int alloc, size, r, max;
+ char *buf, *buf2;
+
CHROOT_IN;
- fd = open (path, O_WRONLY | O_CREAT | O_NOCTTY | O_NONBLOCK, 0666);
+ fd = open (path, O_RDONLY);
CHROOT_OUT;
if (fd == -1) {
reply_with_perror ("open: %s", path);
- close (fd);
+ return NULL;
+ }
+
+ /* Read up to GUESTFS_MESSAGE_MAX - <overhead> bytes. If it's
+ * larger than that, we need to return an error instead (for
+ * correctness).
+ */
+ max = GUESTFS_MESSAGE_MAX - 1000;
+ buf = NULL;
+ size = alloc = 0;
+
+ for (;;) {
+ if (size >= alloc) {
+ alloc += 8192;
+ if (alloc > max) {
+ reply_with_error ("cat: %s: file is too large for message buffer",
+ path);
+ free (buf);
+ close (fd);
+ return NULL;
+ }
+ buf2 = realloc (buf, alloc);
+ if (buf2 == NULL) {
+ reply_with_perror ("realloc");
+ free (buf);
+ close (fd);
+ return NULL;
+ }
+ buf = buf2;
+ }
+
+ r = read (fd, buf + size, alloc - size);
+ if (r == -1) {
+ reply_with_perror ("read: %s", path);
+ free (buf);
+ close (fd);
+ return NULL;
+ }
+ if (r == 0) {
+ buf[size] = '\0';
+ break;
+ }
+ if (r > 0)
+ size += r;
+ }
+
+ if (close (fd) == -1) {
+ reply_with_perror ("close: %s", path);
+ free (buf);
+ return NULL;
+ }
+
+ return buf; /* caller will free */
+}
+
+char **
+do_read_lines (const char *path)
+{
+ char **r = NULL;
+ int size = 0, alloc = 0;
+ FILE *fp;
+ char *line = NULL;
+ size_t len = 0;
+ ssize_t n;
+
+ CHROOT_IN;
+ fp = fopen (path, "r");
+ CHROOT_OUT;
+
+ if (!fp) {
+ reply_with_perror ("fopen: %s", path);
+ return NULL;
+ }
+
+ while ((n = getline (&line, &len, fp)) != -1) {
+ /* Remove either LF or CRLF. */
+ if (n >= 2 && line[n-2] == '\r' && line[n-1] == '\n')
+ line[n-2] = '\0';
+ else if (n >= 1 && line[n-1] == '\n')
+ line[n-1] = '\0';
+
+ if (add_string (&r, &size, &alloc, line) == -1) {
+ free (line);
+ fclose (fp);
+ return NULL;
+ }
+ }
+
+ free (line);
+
+ if (add_string (&r, &size, &alloc, NULL) == -1) {
+ fclose (fp);
+ return NULL;
+ }
+
+ if (fclose (fp) == EOF) {
+ reply_with_perror ("fclose: %s", path);
+ free_strings (r);
+ return NULL;
+ }
+
+ return r;
+}
+
+int
+do_rm (const char *path)
+{
+ int r;
+
+ CHROOT_IN;
+ r = unlink (path);
+ CHROOT_OUT;
+
+ if (r == -1) {
+ reply_with_perror ("unlink: %s", path);
return -1;
}
- if (futimens (fd, NULL) == -1) {
- reply_with_perror ("futimens: %s", path);
+ return 0;
+}
+
+int
+do_chmod (int mode, const char *path)
+{
+ int r;
+
+ CHROOT_IN;
+ r = chmod (path, mode);
+ CHROOT_OUT;
+
+ if (r == -1) {
+ reply_with_perror ("chmod: %s: 0%o", path, mode);
+ return -1;
+ }
+
+ return 0;
+}
+
+int
+do_chown (int owner, int group, const char *path)
+{
+ int r;
+
+ CHROOT_IN;
+ r = chown (path, owner, group);
+ CHROOT_OUT;
+
+ if (r == -1) {
+ reply_with_perror ("chown: %s: %d.%d", path, owner, group);
+ return -1;
+ }
+
+ return 0;
+}
+
+int
+do_lchown (int owner, int group, const char *path)
+{
+ int r;
+
+ CHROOT_IN;
+ r = lchown (path, owner, group);
+ CHROOT_OUT;
+
+ if (r == -1) {
+ reply_with_perror ("lchown: %s: %d.%d", path, owner, group);
+ return -1;
+ }
+
+ return 0;
+}
+
+int
+do_exists (const char *path)
+{
+ int r;
+
+ CHROOT_IN;
+ r = access (path, F_OK);
+ CHROOT_OUT;
+
+ return r == 0;
+}
+
+int
+do_is_file (const char *path)
+{
+ int r;
+ struct stat buf;
+
+ CHROOT_IN;
+ r = lstat (path, &buf);
+ CHROOT_OUT;
+
+ if (r == -1) {
+ if (errno != ENOENT && errno != ENOTDIR) {
+ reply_with_perror ("stat: %s", path);
+ return -1;
+ }
+ else
+ return 0; /* Not a file. */
+ }
+
+ return S_ISREG (buf.st_mode);
+}
+
+int
+do_write_file (const char *path, const char *content, int size)
+{
+ int fd;
+
+ if (size == 0)
+ size = strlen (content);
+
+ CHROOT_IN;
+ fd = open (path, O_WRONLY | O_TRUNC | O_CREAT | O_NOCTTY, 0666);
+ CHROOT_OUT;
+
+ if (fd == -1) {
+ reply_with_perror ("open: %s", path);
+ return -1;
+ }
+
+ if (xwrite (fd, content, size) == -1) {
+ reply_with_perror ("write");
close (fd);
return -1;
}
- close (fd);
+ if (close (fd) == -1) {
+ reply_with_perror ("close: %s", path);
+ return -1;
+ }
+
return 0;
}
char *
-do_cat (const char *path)
+do_read_file (const char *path, size_t *size_r)
+{
+ int fd;
+ struct stat statbuf;
+ char *r;
+
+ CHROOT_IN;
+ fd = open (path, O_RDONLY);
+ CHROOT_OUT;
+
+ if (fd == -1) {
+ reply_with_perror ("open: %s", path);
+ return NULL;
+ }
+
+ if (fstat (fd, &statbuf) == -1) {
+ reply_with_perror ("fstat: %s", path);
+ close (fd);
+ return NULL;
+ }
+
+ *size_r = statbuf.st_size;
+ /* The actual limit on messages is smaller than this. This
+ * check just limits the amount of memory we'll try and allocate
+ * here. If the message is larger than the real limit, that will
+ * be caught later when we try to serialize the message.
+ */
+ if (*size_r >= GUESTFS_MESSAGE_MAX) {
+ reply_with_error ("read_file: %s: file is too large for the protocol, use guestfs_download instead", path);
+ close (fd);
+ return NULL;
+ }
+ r = malloc (*size_r);
+ if (r == NULL) {
+ reply_with_perror ("malloc");
+ close (fd);
+ return NULL;
+ }
+
+ if (xread (fd, r, *size_r) == -1) {
+ reply_with_perror ("read: %s", path);
+ close (fd);
+ free (r);
+ return NULL;
+ }
+
+ if (close (fd) == -1) {
+ reply_with_perror ("close: %s", path);
+ free (r);
+ return NULL;
+ }
+
+ return r;
+}
+
+char *
+do_pread (const char *path, int count, int64_t offset, size_t *size_r)
{
- reply_with_error ("cat command is not yet implemented");
- return NULL;
+ int fd;
+ ssize_t r;
+ char *buf;
+
+ /* The actual limit on messages is smaller than this. This check
+ * just limits the amount of memory we'll try and allocate in the
+ * function. If the message is larger than the real limit, that
+ * will be caught later when we try to serialize the message.
+ */
+ if (count >= GUESTFS_MESSAGE_MAX) {
+ reply_with_error ("pread: %s: count is too large for the protocol, use smaller reads", path);
+ return NULL;
+ }
+
+ CHROOT_IN;
+ fd = open (path, O_RDONLY);
+ CHROOT_OUT;
+
+ if (fd == -1) {
+ reply_with_perror ("open: %s", path);
+ return NULL;
+ }
+
+ buf = malloc (count);
+ if (buf == NULL) {
+ reply_with_perror ("malloc");
+ close (fd);
+ return NULL;
+ }
+
+ r = pread (fd, buf, count, offset);
+ if (r == -1) {
+ reply_with_perror ("pread: %s", path);
+ close (fd);
+ free (buf);
+ return NULL;
+ }
+
+ if (close (fd) == -1) {
+ reply_with_perror ("close: %s", path);
+ close (fd);
+ free (buf);
+ return NULL;
+ }
+
+ *size_r = r;
+ return buf;
+}
+
+/* This runs the 'file' command. */
+char *
+do_file (const char *path)
+{
+ char *out, *err;
+ int r, freeit = 0;
+ char *buf;
+ int len;
+
+ if (strncmp (path, "/dev/", 5) == 0)
+ buf = (char *) path;
+ else {
+ buf = sysroot_path (path);
+ if (!buf) {
+ reply_with_perror ("malloc");
+ return NULL;
+ }
+ freeit = 1;
+ }
+
+ /* file(1) manpage claims "file returns 0 on success, and non-zero on
+ * error", but this is evidently not true. It always returns 0, in
+ * every scenario I can think up. So check the target is readable
+ * first.
+ */
+ if (access (buf, R_OK) == -1) {
+ if (freeit) free (buf);
+ reply_with_perror ("access: %s", path);
+ return NULL;
+ }
+
+ r = command (&out, &err, "file", "-zbsL", buf, NULL);
+ if (freeit) free (buf);
+
+ if (r == -1) {
+ free (out);
+ reply_with_error ("file: %s: %s", path, err);
+ free (err);
+ return NULL;
+ }
+ free (err);
+
+ /* We need to remove the trailing \n from output of file(1). */
+ len = strlen (out);
+ if (out[len-1] == '\n')
+ out[len-1] = '\0';
+
+ return out; /* caller frees */
+}
+
+/* zcat | file */
+char *
+do_zfile (const char *method, const char *path)
+{
+ int len;
+ const char *zcat;
+ char *cmd;
+ FILE *fp;
+ char line[256];
+
+ if (strcmp (method, "gzip") == 0 || strcmp (method, "compress") == 0)
+ zcat = "zcat";
+ else if (strcmp (method, "bzip2") == 0)
+ zcat = "bzcat";
+ else {
+ reply_with_error ("zfile: unknown method");
+ return NULL;
+ }
+
+ if (asprintf_nowarn (&cmd, "%s %R | file -bsL -", zcat, path) == -1) {
+ reply_with_perror ("asprintf");
+ return NULL;
+ }
+
+ if (verbose)
+ fprintf (stderr, "%s\n", cmd);
+
+ fp = popen (cmd, "r");
+ if (fp == NULL) {
+ reply_with_perror ("%s", cmd);
+ free (cmd);
+ return NULL;
+ }
+
+ free (cmd);
+
+ if (fgets (line, sizeof line, fp) == NULL) {
+ reply_with_perror ("zfile: fgets");
+ fclose (fp);
+ return NULL;
+ }
+
+ if (fclose (fp) == -1) {
+ reply_with_perror ("zfile: fclose");
+ return NULL;
+ }
+
+ len = strlen (line);
+ if (len > 0 && line[len-1] == '\n')
+ line[len-1] = '\0';
+
+ return strdup (line);
}
git.annexia.org / libguestfs.git / blobdiff