Move the code handling Windows paths from virt-edit to a common file, so that can be shared by various tools. Mostly code motion, with a minimum touch (the additional guestfs_h* parameter in mount_drive_letter) to make it build and work. --- edit/Makefile.am | 4 +- edit/edit.c | 104 +----------------------------------------- fish/windows.c | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fish/windows.h | 44 ++++++++++++++++++ po/POTFILES | 1 + 5 files changed, 184 insertions(+), 104 deletions(-) create mode 100644 fish/windows.c create mode 100644 fish/windows.h diff --git a/edit/Makefile.am b/edit/Makefile.am index 1d51095..cb19bec 100644 --- a/edit/Makefile.am +++ b/edit/Makefile.am @@ -33,7 +33,9 @@ SHARED_SOURCE_FILES = \ ../fish/options.h \ ../fish/options.c \ ../fish/uri.h \ - ../fish/uri.c + ../fish/uri.c \ + ../fish/windows.h \ + ../fish/windows.c virt_edit_SOURCES = \ $(SHARED_SOURCE_FILES) \ diff --git a/edit/edit.c b/edit/edit.c index 733c911..d4ce747 100644 --- a/edit/edit.c +++ b/edit/edit.c @@ -37,6 +37,7 @@ #include "guestfs.h" #include "options.h" +#include "windows.h" /* Currently open libguestfs handle. */ guestfs_h *g; @@ -56,8 +57,6 @@ static void edit_files (int argc, char *argv[]); static void edit (const char *filename, const char *root); static char *edit_interactively (const char *tmpfile); static char *edit_non_interactively (const char *tmpfile); -static int is_windows (guestfs_h *g, const char *root); -static char *windows_path (guestfs_h *g, const char *root, const char *filename); static char *generate_random_name (const char *filename); static char *generate_backup_name (const char *filename); @@ -527,107 +526,6 @@ edit_non_interactively (const char *tmpfile) return ret; /* caller will free */ } -static int -is_windows (guestfs_h *g, const char *root) -{ - int w; - CLEANUP_FREE char *type = guestfs_inspect_get_type (g, root); - if (!type) - return 0; - - w = STREQ (type, "windows"); - return w; -} - -static void mount_drive_letter (char drive_letter, const char *root); - -static char * -windows_path (guestfs_h *g, const char *root, const char *path) -{ - char *ret; - size_t i; - - /* If there is a drive letter, rewrite the path. */ - if (c_isalpha (path[0]) && path[1] == ':') { - char drive_letter = c_tolower (path[0]); - /* This returns the newly allocated string. */ - mount_drive_letter (drive_letter, root); - ret = strdup (path + 2); - if (ret == NULL) { - perror ("strdup"); - exit (EXIT_FAILURE); - } - } - else if (!*path) { - ret = strdup ("/"); - if (ret == NULL) { - perror ("strdup"); - exit (EXIT_FAILURE); - } - } - else { - ret = strdup (path); - if (ret == NULL) { - perror ("strdup"); - exit (EXIT_FAILURE); - } - } - - /* Blindly convert any backslashes into forward slashes. Is this good? */ - for (i = 0; i < strlen (ret); ++i) - if (ret[i] == '\\') - ret[i] = '/'; - - char *t = guestfs_case_sensitive_path (g, ret); - free (ret); - ret = t; - if (ret == NULL) - exit (EXIT_FAILURE); - - return ret; -} - -static void -mount_drive_letter (char drive_letter, const char *root) -{ - char *device; - size_t i; - - /* Resolve the drive letter using the drive mappings table. */ - CLEANUP_FREE_STRING_LIST char **drives = - guestfs_inspect_get_drive_mappings (g, root); - if (drives == NULL || drives[0] == NULL) { - fprintf (stderr, _("%s: to use Windows drive letters, this must be a Windows guest\n"), - program_name); - exit (EXIT_FAILURE); - } - - device = NULL; - for (i = 0; drives[i] != NULL; i += 2) { - if (c_tolower (drives[i][0]) == drive_letter && drives[i][1] == '\0') { - device = drives[i+1]; - break; - } - } - - if (device == NULL) { - fprintf (stderr, _("%s: drive '%c:' not found.\n"), - program_name, drive_letter); - exit (EXIT_FAILURE); - } - - /* Unmount current disk and remount device. */ - if (guestfs_umount_all (g) == -1) - exit (EXIT_FAILURE); - - if (guestfs_mount (g, device, "/") == -1) - exit (EXIT_FAILURE); - - /* Don't need to free (device) because that string was in the - * drives array. - */ -} - static char random_char (void) { diff --git a/fish/windows.c b/fish/windows.c new file mode 100644 index 0000000..ddf2af1 --- /dev/null +++ b/fish/windows.c @@ -0,0 +1,135 @@ +/* libguestfs - shared Windows path for tools + * Copyright (C) 2009-2014 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 + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <config.h> + +#include "windows.h" + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <locale.h> +#include <langinfo.h> +#include <libintl.h> + +#include "guestfs-internal-frontend.h" + +#include "c-ctype.h" + +static void mount_drive_letter (guestfs_h *g, char drive_letter, + const char *root); + +int +is_windows (guestfs_h *g, const char *root) +{ + int w; + CLEANUP_FREE char *type = guestfs_inspect_get_type (g, root); + if (!type) + return 0; + + w = STREQ (type, "windows"); + return w; +} + +char * +windows_path (guestfs_h *g, const char *root, const char *path) +{ + char *ret; + size_t i; + + /* If there is a drive letter, rewrite the path. */ + if (c_isalpha (path[0]) && path[1] == ':') { + char drive_letter = c_tolower (path[0]); + /* This returns the newly allocated string. */ + mount_drive_letter (g, drive_letter, root); + ret = strdup (path + 2); + if (ret == NULL) { + perror ("strdup"); + exit (EXIT_FAILURE); + } + } + else if (!*path) { + ret = strdup ("/"); + if (ret == NULL) { + perror ("strdup"); + exit (EXIT_FAILURE); + } + } + else { + ret = strdup (path); + if (ret == NULL) { + perror ("strdup"); + exit (EXIT_FAILURE); + } + } + + /* Blindly convert any backslashes into forward slashes. Is this good? */ + for (i = 0; i < strlen (ret); ++i) + if (ret[i] == '\\') + ret[i] = '/'; + + char *t = guestfs_case_sensitive_path (g, ret); + free (ret); + ret = t; + if (ret == NULL) + exit (EXIT_FAILURE); + + return ret; +} + +static void +mount_drive_letter (guestfs_h *g, char drive_letter, const char *root) +{ + char *device; + size_t i; + + /* Resolve the drive letter using the drive mappings table. */ + CLEANUP_FREE_STRING_LIST char **drives = + guestfs_inspect_get_drive_mappings (g, root); + if (drives == NULL || drives[0] == NULL) { + fprintf (stderr, _("%s: to use Windows drive letters, this must be a Windows guest\n"), + program_name); + exit (EXIT_FAILURE); + } + + device = NULL; + for (i = 0; drives[i] != NULL; i += 2) { + if (c_tolower (drives[i][0]) == drive_letter && drives[i][1] == '\0') { + device = drives[i+1]; + break; + } + } + + if (device == NULL) { + fprintf (stderr, _("%s: drive '%c:' not found.\n"), + program_name, drive_letter); + exit (EXIT_FAILURE); + } + + /* Unmount current disk and remount device. */ + if (guestfs_umount_all (g) == -1) + exit (EXIT_FAILURE); + + if (guestfs_mount (g, device, "/") == -1) + exit (EXIT_FAILURE); + + /* Don't need to free (device) because that string was in the + * drives array. + */ +} diff --git a/fish/windows.h b/fish/windows.h new file mode 100644 index 0000000..bb68634 --- /dev/null +++ b/fish/windows.h @@ -0,0 +1,44 @@ +/* libguestfs - shared Windows path for tools + * Copyright (C) 2009-2014 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 + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef FISH_WINDOWS_H +#define FISH_WINDOWS_H + +#include <guestfs.h> + +/** + * Checks whether 'root' is a Windows installation. + * + * This relies on an already being done introspection. + */ +extern int is_windows (guestfs_h *g, const char *root); + +/** + * Resolves 'path' as possible Windows path according to 'root', + * giving a new path that can be used in libguestfs API calls. + * + * Notes: + * - 'root' must be a Windows installation + * - relies on an already being done introspection + * - will unmount all the existing mount points and mount the Windows root + * - will exit() on memory allocation failures, and if it is not possible + * to get the true path on case-insensitive filesystems + */ +extern char *windows_path (guestfs_h *g, const char *root, const char *path); + +#endif diff --git a/po/POTFILES b/po/POTFILES index 3d208d5..d40cf9b 100644 --- a/po/POTFILES +++ b/po/POTFILES @@ -160,6 +160,7 @@ fish/supported.c fish/tilde.c fish/time.c fish/uri.c +fish/windows.c format/format.c fuse/guestmount.c fuse/guestunmount.c -- 1.9.3

Do not unconditionally exit if guestfs_case_sensitive_path, but let windows_path still return null. Make virt-edit then check for that, and eventually exit on its own. --- edit/edit.c | 5 ++++- fish/windows.c | 3 +-- fish/windows.h | 3 +-- 3 files changed, 6 insertions(+), 5 deletions(-) diff --git a/edit/edit.c b/edit/edit.c index cd91b5f..1f5ec7b 100644 --- a/edit/edit.c +++ b/edit/edit.c @@ -335,9 +335,12 @@ edit (const char *filename, const char *root) CLEANUP_FREE char *backupname = NULL; /* Windows? Special handling is required. */ - if (root != NULL && is_windows (g, root)) + if (root != NULL && is_windows (g, root)) { filename = filename_to_free = windows_path (g, root, filename, 0 /* not read only */); + if (filename == NULL) + exit (EXIT_FAILURE); + } /* Download the file to a temporary. */ fd = mkstemp (tmpfile); diff --git a/fish/windows.c b/fish/windows.c index 06dcab3..04ead2f 100644 --- a/fish/windows.c +++ b/fish/windows.c @@ -84,11 +84,10 @@ windows_path (guestfs_h *g, const char *root, const char *path, int readonly) if (ret[i] == '\\') ret[i] = '/'; + /* If this fails, we want to return NULL. */ char *t = guestfs_case_sensitive_path (g, ret); free (ret); ret = t; - if (ret == NULL) - exit (EXIT_FAILURE); return ret; } diff --git a/fish/windows.h b/fish/windows.h index 5543182..c543604 100644 --- a/fish/windows.h +++ b/fish/windows.h @@ -37,8 +37,7 @@ extern int is_windows (guestfs_h *g, const char *root); * - relies on an already being done introspection * - will unmount all the existing mount points and mount the Windows root * (according to 'readonly') - * - will exit() on memory allocation failures, and if it is not possible - * to get the true path on case-insensitive filesystems + * - will exit() on memory allocation failures */ extern char *windows_path (guestfs_h *g, const char *root, const char *path, int readonly); -- 1.9.3

Move the implementation of file editing using editor to an own file, so that can be shared by different tools. Mostly code motion. --- fish/Makefile.am | 2 + fish/edit.c | 125 ++----------------------------------------- fish/file-edit.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fish/file-edit.h | 32 +++++++++++ po/POTFILES | 1 + 5 files changed, 198 insertions(+), 120 deletions(-) create mode 100644 fish/file-edit.c create mode 100644 fish/file-edit.h diff --git a/fish/Makefile.am b/fish/Makefile.am index c02f703..d28a94b 100644 --- a/fish/Makefile.am +++ b/fish/Makefile.am @@ -87,6 +87,8 @@ guestfish_SOURCES = \ echo.c \ edit.c \ events.c \ + file-edit.c \ + file-edit.h \ fish.c \ fish.h \ glob.c \ diff --git a/fish/edit.c b/fish/edit.c index bd02f4b..5b851e7 100644 --- a/fish/edit.c +++ b/fish/edit.c @@ -22,29 +22,20 @@ #include <stdlib.h> #include <string.h> #include <unistd.h> -#include <fcntl.h> #include <inttypes.h> #include <libintl.h> -#include <sys/types.h> -#include <sys/stat.h> -#include <assert.h> #include "fish.h" - -static char *generate_random_name (const char *filename); +#include "file-edit.h" /* guestfish edit command, suggested by Ján Ondrej, implemented by RWMJ */ int run_edit (const char *cmd, size_t argc, char *argv[]) { - CLEANUP_FREE char *tmpdir = guestfs_get_tmpdir (g); - CLEANUP_UNLINK_FREE char *filename = NULL; - char buf[256]; const char *editor; - CLEANUP_FREE char *remotefilename = NULL, *newname = NULL; - struct stat oldstat, newstat; - int r, fd; + CLEANUP_FREE char *remotefilename = NULL; + int r; if (argc != 1) { fprintf (stderr, _("use '%s filename' to edit a file\n"), cmd); @@ -67,113 +58,7 @@ run_edit (const char *cmd, size_t argc, char *argv[]) if (remotefilename == NULL) return -1; - /* Download the file and write it to a temporary. */ - if (asprintf (&filename, "%s/guestfishXXXXXX", tmpdir) == -1) { - perror ("asprintf"); - return -1; - } - - fd = mkstemp (filename); - if (fd == -1) { - perror ("mkstemp"); - return -1; - } - - snprintf (buf, sizeof buf, "/dev/fd/%d", fd); - - if (guestfs_download (g, remotefilename, buf) == -1) { - close (fd); - return -1; - } - - if (close (fd) == -1) { - perror (filename); - return -1; - } - - /* Get the old stat. */ - if (stat (filename, &oldstat) == -1) { - perror (filename); - return -1; - } - - /* Edit it. */ - /* XXX Safe? */ - snprintf (buf, sizeof buf, "%s %s", editor, filename); - - r = system (buf); - if (r != 0) { - perror (buf); - return -1; - } - - /* Get the new stat. */ - if (stat (filename, &newstat) == -1) { - perror (filename); - return -1; - } - - /* Changed? */ - if (oldstat.st_ctime == newstat.st_ctime && - oldstat.st_size == newstat.st_size) - return 0; - - /* Upload to a new file in the same directory, so if it fails we - * don't end up with a partially written file. Give the new file - * a completely random name so we have only a tiny chance of - * overwriting some existing file. - */ - newname = generate_random_name (remotefilename); - if (!newname) - return -1; - - /* Write new content. */ - if (guestfs_upload (g, filename, newname) == -1) - return -1; - - /* Set the permissions, UID, GID and SELinux context of the new - * file to match the old file (RHBZ#788641). - */ - if (guestfs_copy_attributes (g, remotefilename, newname, - GUESTFS_COPY_ATTRIBUTES_ALL, 1, -1) == -1) - return -1; - - if (guestfs_mv (g, newname, remotefilename) == -1) - return -1; - - return 0; -} - -static char -random_char (void) -{ - char c[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; - return c[random () % (sizeof c - 1)]; -} - -static char * -generate_random_name (const char *filename) -{ - char *ret, *p; - size_t i; - - ret = malloc (strlen (filename) + 16); - if (!ret) { - perror ("malloc"); - return NULL; - } - strcpy (ret, filename); - - p = strrchr (ret, '/'); - assert (p); - p++; - - /* Because of "+ 16" above, there should be enough space in the - * output buffer to write 8 random characters here. - */ - for (i = 0; i < 8; ++i) - *p++ = random_char (); - *p++ = '\0'; + r = edit_file_editor (g, remotefilename, editor); - return ret; /* caller will free */ + return r; } diff --git a/fish/file-edit.c b/fish/file-edit.c new file mode 100644 index 0000000..ec707a9 --- /dev/null +++ b/fish/file-edit.c @@ -0,0 +1,158 @@ +/* libguestfs - shared file editing + * Copyright (C) 2009-2014 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 + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <config.h> + +#include "file-edit.h" + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <locale.h> +#include <langinfo.h> +#include <libintl.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <assert.h> + +#include "guestfs-internal-frontend.h" + +static char *generate_random_name (const char *filename); + +int +edit_file_editor (guestfs_h *g, const char *filename, const char *editor) +{ + CLEANUP_FREE char *tmpdir = guestfs_get_tmpdir (g); + CLEANUP_UNLINK_FREE char *tmpfilename = NULL; + char buf[256]; + CLEANUP_FREE char *newname = NULL; + struct stat oldstat, newstat; + int r, fd; + + /* Download the file and write it to a temporary. */ + if (asprintf (&tmpfilename, "%s/libguestfsXXXXXX", tmpdir) == -1) { + perror ("asprintf"); + return -1; + } + + fd = mkstemp (tmpfilename); + if (fd == -1) { + perror ("mkstemp"); + return -1; + } + + snprintf (buf, sizeof buf, "/dev/fd/%d", fd); + + if (guestfs_download (g, filename, buf) == -1) { + close (fd); + return -1; + } + + if (close (fd) == -1) { + perror (tmpfilename); + return -1; + } + + /* Get the old stat. */ + if (stat (tmpfilename, &oldstat) == -1) { + perror (tmpfilename); + return -1; + } + + /* Edit it. */ + /* XXX Safe? */ + snprintf (buf, sizeof buf, "%s %s", editor, filename); + + r = system (buf); + if (r != 0) { + perror (buf); + return -1; + } + + /* Get the new stat. */ + if (stat (tmpfilename, &newstat) == -1) { + perror (tmpfilename); + return -1; + } + + /* Changed? */ + if (oldstat.st_ctime == newstat.st_ctime && + oldstat.st_size == newstat.st_size) + return 0; + + /* Upload to a new file in the same directory, so if it fails we + * don't end up with a partially written file. Give the new file + * a completely random name so we have only a tiny chance of + * overwriting some existing file. + */ + newname = generate_random_name (filename); + if (!newname) + return -1; + + /* Write new content. */ + if (guestfs_upload (g, tmpfilename, newname) == -1) + return -1; + + /* Set the permissions, UID, GID and SELinux context of the new + * file to match the old file (RHBZ#788641). + */ + if (guestfs_copy_attributes (g, filename, newname, + GUESTFS_COPY_ATTRIBUTES_ALL, 1, -1) == -1) + return -1; + + if (guestfs_mv (g, newname, filename) == -1) + return -1; + + return 0; +} + +static char +random_char (void) +{ + const char c[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; + return c[random () % (sizeof c - 1)]; +} + +static char * +generate_random_name (const char *filename) +{ + char *ret, *p; + size_t i; + + ret = malloc (strlen (filename) + 16); + if (!ret) { + perror ("malloc"); + return NULL; + } + strcpy (ret, filename); + + p = strrchr (ret, '/'); + assert (p); + p++; + + /* Because of "+ 16" above, there should be enough space in the + * output buffer to write 8 random characters here. + */ + for (i = 0; i < 8; ++i) + *p++ = random_char (); + *p++ = '\0'; + + return ret; /* caller will free */ +} diff --git a/fish/file-edit.h b/fish/file-edit.h new file mode 100644 index 0000000..eff1c7d --- /dev/null +++ b/fish/file-edit.h @@ -0,0 +1,32 @@ +/* libguestfs - shared file editing + * Copyright (C) 2009-2014 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 + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef FISH_FILE_EDIT_H +#define FISH_FILE_EDIT_H + +#include <guestfs.h> + +/** + * Edit 'filename' using the specified 'editor' application. + * + * Returns -1 for failure, 0 otherwise. + */ +extern int edit_file_editor (guestfs_h *g, const char *filename, + const char *editor); + +#endif diff --git a/po/POTFILES b/po/POTFILES index d40cf9b..a31cc88 100644 --- a/po/POTFILES +++ b/po/POTFILES @@ -135,6 +135,7 @@ fish/echo.c fish/edit.c fish/event-names.c fish/events.c +fish/file-edit.c fish/fish.c fish/glob.c fish/help.c -- 1.9.3

Change the return value of edit_file_editor to 1, in case the editor did not change the (temporary) file. --- fish/edit.c | 2 +- fish/file-edit.c | 2 +- fish/file-edit.h | 3 ++- 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/fish/edit.c b/fish/edit.c index 0170daf..f43ef3b 100644 --- a/fish/edit.c +++ b/fish/edit.c @@ -60,5 +60,5 @@ run_edit (const char *cmd, size_t argc, char *argv[]) r = edit_file_editor (g, remotefilename, editor, NULL); - return r; + return r == -1 ? -1 : 0; } diff --git a/fish/file-edit.c b/fish/file-edit.c index 8efa452..3a9dd2d 100644 --- a/fish/file-edit.c +++ b/fish/file-edit.c @@ -101,7 +101,7 @@ edit_file_editor (guestfs_h *g, const char *filename, const char *editor, /* Changed? */ if (oldstat.st_ctime == newstat.st_ctime && oldstat.st_size == newstat.st_size) - return 0; + return 1; /* Upload to a new file in the same directory, so if it fails we * don't end up with a partially written file. Give the new file diff --git a/fish/file-edit.h b/fish/file-edit.h index 6622b3a..1d401c6 100644 --- a/fish/file-edit.h +++ b/fish/file-edit.h @@ -26,7 +26,8 @@ * If 'backup_extension' is not null, then a copy of 'filename' is saved * with 'backup_extension' appended to its file name. * - * Returns -1 for failure, 0 otherwise. + * Returns -1 for failure, 0 on success, 1 if the editor did not change + * the file (e.g. the user closed the editor without saving). */ extern int edit_file_editor (guestfs_h *g, const char *filename, const char *editor, const char *backup_extension); -- 1.9.3

Add the perl file editing, mostly based in the virt-edit implementation. This introduces a mild code duplication with edit_file_editor; will deal with it in a later commit. --- fish/file-edit.c | 110 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fish/file-edit.h | 11 ++++++ 2 files changed, 121 insertions(+) diff --git a/fish/file-edit.c b/fish/file-edit.c index e2298eb..fa68626 100644 --- a/fish/file-edit.c +++ b/fish/file-edit.c @@ -159,6 +159,116 @@ edit_file_editor (guestfs_h *g, const char *filename, const char *editor, return 0; } +int +edit_file_perl (guestfs_h *g, const char *filename, const char *perl_expr, + const char *backup_extension) +{ + CLEANUP_FREE char *tmpdir = guestfs_get_tmpdir (g); + CLEANUP_UNLINK_FREE char *tmpfilename = NULL; + char buf[256]; + CLEANUP_FREE char *newname = NULL; + CLEANUP_FREE char *cmd = NULL; + CLEANUP_FREE char *outfile = NULL; + int r, fd; + + /* Download the file and write it to a temporary. */ + if (asprintf (&tmpfilename, "%s/libguestfsXXXXXX", tmpdir) == -1) { + perror ("asprintf"); + return -1; + } + + fd = mkstemp (tmpfilename); + if (fd == -1) { + perror ("mkstemp"); + return -1; + } + + snprintf (buf, sizeof buf, "/dev/fd/%d", fd); + + if (guestfs_download (g, filename, buf) == -1) { + close (fd); + return -1; + } + + if (close (fd) == -1) { + perror (tmpfilename); + return -1; + } + + if (asprintf (&outfile, "%s.out", tmpfilename) == -1) { + perror ("asprintf"); + return -1; + } + + /* Pass the expression to Perl via the environment. This sidesteps + * any quoting problems with the already complex Perl command line. + */ + setenv ("virt_edit_expr", perl_expr, 1); + + /* Call out to a canned Perl script. */ + if (asprintf (&cmd, + "perl -e '" + "$lineno = 0; " + "$expr = $ENV{virt_edit_expr}; " + "while (<STDIN>) { " + " $lineno++; " + " eval $expr; " + " die if $@; " + " print STDOUT $_ or die \"print: $!\"; " + "} " + "close STDOUT or die \"close: $!\"; " + "' < %s > %s", + tmpfilename, outfile) == -1) { + perror ("asprintf"); + return -1; + } + + r = system (cmd); + if (r == -1 || WEXITSTATUS (r) != 0) + return -1; + + if (rename (outfile, tmpfilename) == -1) { + perror ("rename"); + return -1; + } + + /* Upload to a new file in the same directory, so if it fails we + * don't end up with a partially written file. Give the new file + * a completely random name so we have only a tiny chance of + * overwriting some existing file. + */ + newname = generate_random_name (filename); + if (!newname) + return -1; + + /* Write new content. */ + if (guestfs_upload (g, tmpfilename, newname) == -1) + return -1; + + /* Set the permissions, UID, GID and SELinux context of the new + * file to match the old file (RHBZ#788641). + */ + if (guestfs_copy_attributes (g, filename, newname, + GUESTFS_COPY_ATTRIBUTES_ALL, 1, -1) == -1) + return -1; + + /* Backup or overwrite the file. */ + if (backup_extension) { + CLEANUP_FREE char *backupname = NULL; + + backupname = generate_backup_name (filename, backup_extension); + if (backupname == NULL) + return -1; + + if (guestfs_mv (g, filename, backupname) == -1) + return -1; + } + if (guestfs_mv (g, newname, filename) == -1) + return -1; + + return 0; +} + static char random_char (void) { diff --git a/fish/file-edit.h b/fish/file-edit.h index 1d401c6..98fc453 100644 --- a/fish/file-edit.h +++ b/fish/file-edit.h @@ -32,4 +32,15 @@ extern int edit_file_editor (guestfs_h *g, const char *filename, const char *editor, const char *backup_extension); +/** + * Edit 'filename' running the specified 'perl_expr' using Perl. + * If 'backup_extension' is not null, then a copy of 'filename' is saved + * with 'backup_extension' appended to its file name. + * + * Returns -1 for failure, 0 otherwise (on success). + */ +extern int edit_file_perl (guestfs_h *g, const char *filename, + const char *perl_expr, + const char *backup_extension); + #endif -- 1.9.3