X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=daemon%2Ffile.c;h=851d9e7cf62373fe030299791e56ff8eba58d63e;hp=1e633d852391448b9a6c659042f80e4968f87db0;hb=8ab8377ef64ec0e2483826388cf7d3c07ffa8ecc;hpb=99bd425a0a8fb02c27e0c22b32dafa804773a7b1 diff --git a/daemon/file.c b/daemon/file.c index 1e633d8..851d9e7 100644 --- a/daemon/file.c +++ b/daemon/file.c @@ -1,5 +1,5 @@ /* 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 @@ -18,8 +18,6 @@ #include -#define _GNU_SOURCE /* for futimens(2) */ - #include #include #include @@ -27,37 +25,414 @@ #include #include +#include "../src/guestfs_protocol.h" #include "daemon.h" #include "actions.h" int -do_touch (const char *path) +do_touch (char *path) { int fd; + int r; + + NEED_ROOT (-1); + ABS_PATH (path, -1); + + CHROOT_IN; + fd = open (path, O_WRONLY | O_CREAT | O_NOCTTY, 0666); + CHROOT_OUT; + + if (fd == -1) { + reply_with_perror ("open: %s", path); + return -1; + } - NEED_ROOT; +#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 (char *path) +{ + int fd; + int alloc, size, r, max; + char *buf, *buf2; + + NEED_ROOT (NULL); + ABS_PATH (path,NULL); + 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 - 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 (char *path) +{ + char **r = NULL; + int size = 0, alloc = 0; + FILE *fp; + char *line = NULL; + size_t len = 0; + ssize_t n; + + NEED_ROOT (NULL); + ABS_PATH (path, NULL); + + 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 (char *path) +{ + int r; + + NEED_ROOT (-1); + ABS_PATH (path, -1); + + 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, char *path) +{ + int r; + + NEED_ROOT (-1); + ABS_PATH (path, -1); + + 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, char *path) +{ + int r; + + NEED_ROOT (-1); + ABS_PATH (path, -1); + + 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_exists (char *path) +{ + int r; + + NEED_ROOT (-1); + ABS_PATH (path, -1); + + CHROOT_IN; + r = access (path, F_OK); + CHROOT_OUT; + + return r == 0; +} + +int +do_is_file (char *path) +{ + int r; + struct stat buf; + + NEED_ROOT (-1); + ABS_PATH (path, -1); + + 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 (char *path, char *content, int size) +{ + int fd; + + NEED_ROOT (-1); + ABS_PATH (path, -1); + + 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; } + +/* This runs the 'file' command. */ +char * +do_file (char *path) +{ + char *out, *err; + int r, freeit = 0; + char *buf; + int len; + + NEED_ROOT_OR_IS_DEVICE (path, NULL); + ABS_PATH (path, NULL); + + 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", "-bsL", 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 (char *method, char *path) +{ + int len; + char *cmd; + FILE *fp; + char line[256]; + + NEED_ROOT (NULL); + ABS_PATH (path, NULL); + + len = 2 * strlen (path) + sysroot_len + 64; + cmd = malloc (len); + if (!cmd) { + reply_with_perror ("malloc"); + return NULL; + } + + if (strcmp (method, "gzip") == 0 || strcmp (method, "compress") == 0) + strcpy (cmd, "zcat"); + else if (strcmp (method, "bzip2") == 0) + strcpy (cmd, "bzcat"); + else { + free (cmd); + reply_with_error ("zfile: unknown method"); + return NULL; + } + + strcat (cmd, " "); + strcat (cmd, sysroot); + shell_quote (cmd + strlen (cmd), len - strlen (cmd), path); + strcat (cmd, " | file -bsL -"); + + 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); +}