[Libguestfs] [PATCH 5/6] lib: Fix guestfs_int_download_to_tmp.
Richard W.M. Jones
rjones at redhat.com
Tue Sep 19 11:38:26 UTC 2017
Since commit 65cfecb0f5344ec92d3f0d3c2ec0538b6b2726e2,
‘guestfs_int_download_to_tmp’ was buggy because it did not deal with
the case where a guest had multiple roots. It cached the downloaded
file under a single name which was not distinguished by which root we
were looking at. As a result, if you inspected (eg.) the icon on such
a guest, then in some circumstances the same icon could be returned
for all roots (incorrectly).
This changes the function in a few ways:
- Don't cache downloaded files. It wasn't a useful feature of the
function in most scenarios. Instead a new name is generated for
every call.
- Use guestfs_int_make_temp_path.
- Allow an extension to be specified.
---
lib/guestfs-internal.h | 2 +-
lib/inspect-apps.c | 12 +++++-------
lib/inspect-icon.c | 36 +++++++++++++++---------------------
3 files changed, 21 insertions(+), 29 deletions(-)
diff --git a/lib/guestfs-internal.h b/lib/guestfs-internal.h
index f3379da7d..66e03c3b8 100644
--- a/lib/guestfs-internal.h
+++ b/lib/guestfs-internal.h
@@ -713,7 +713,7 @@ extern int guestfs_int_set_backend (guestfs_h *g, const char *method);
} while (0)
/* inspect.c */
-extern char *guestfs_int_download_to_tmp (guestfs_h *g, const char *filename, const char *basename, uint64_t max_size);
+extern char *guestfs_int_download_to_tmp (guestfs_h *g, const char *filename, const char *extension, uint64_t max_size);
/* dbdump.c */
typedef int (*guestfs_int_db_dump_callback) (guestfs_h *g, const unsigned char *key, size_t keylen, const unsigned char *value, size_t valuelen, void *opaque);
diff --git a/lib/inspect-apps.c b/lib/inspect-apps.c
index b721595da..f0cf16b38 100644
--- a/lib/inspect-apps.c
+++ b/lib/inspect-apps.c
@@ -370,14 +370,12 @@ list_applications_rpm (guestfs_h *g, const char *root)
struct guestfs_application2_list *apps = NULL;
struct read_package_data data;
- Name = guestfs_int_download_to_tmp (g,
- "/var/lib/rpm/Name", "rpm_Name",
+ Name = guestfs_int_download_to_tmp (g, "/var/lib/rpm/Name", NULL,
MAX_PKG_DB_SIZE);
if (Name == NULL)
goto error;
- Packages = guestfs_int_download_to_tmp (g,
- "/var/lib/rpm/Packages", "rpm_Packages",
+ Packages = guestfs_int_download_to_tmp (g, "/var/lib/rpm/Packages", NULL,
MAX_PKG_DB_SIZE);
if (Packages == NULL)
goto error;
@@ -429,7 +427,7 @@ list_applications_deb (guestfs_h *g, const char *root)
char **continuation_field = NULL;
size_t continuation_field_len = 0;
- status = guestfs_int_download_to_tmp (g, "/var/lib/dpkg/status", "status",
+ status = guestfs_int_download_to_tmp (g, "/var/lib/dpkg/status", NULL,
MAX_PKG_DB_SIZE);
if (status == NULL)
return NULL;
@@ -605,7 +603,7 @@ list_applications_pacman (guestfs_h *g, const char *root)
fname = safe_malloc (g, strlen (curr->name) + path_len + 1);
sprintf (fname, "/var/lib/pacman/local/%s/desc", curr->name);
free (desc_file);
- desc_file = guestfs_int_download_to_tmp (g, fname, curr->name, 8192);
+ desc_file = guestfs_int_download_to_tmp (g, fname, NULL, 8192);
/* The desc files are small (4K). If the desc file does not exist or is
* larger than the 8K limit we've used, the database is probably corrupted,
@@ -714,7 +712,7 @@ list_applications_apk (guestfs_h *g, const char *root)
*url = NULL, *description = NULL;
installed = guestfs_int_download_to_tmp (g, "/lib/apk/db/installed",
- "installed", MAX_PKG_DB_SIZE);
+ NULL, MAX_PKG_DB_SIZE);
if (installed == NULL)
return NULL;
diff --git a/lib/inspect-icon.c b/lib/inspect-icon.c
index c45761041..3e44b23eb 100644
--- a/lib/inspect-icon.c
+++ b/lib/inspect-icon.c
@@ -234,7 +234,7 @@ get_png (guestfs_h *g, const char *filename, size_t *size_r, size_t max_size)
if (max_size == 0)
max_size = 4 * w * h;
- local = guestfs_int_download_to_tmp (g, real, "icon", max_size);
+ local = guestfs_int_download_to_tmp (g, real, "png", max_size);
if (!local)
return NOT_FOUND;
@@ -385,7 +385,7 @@ icon_cirros (guestfs_h *g, size_t *size_r)
if (!STRPREFIX (type, "ASCII text"))
return NOT_FOUND;
- local = guestfs_int_download_to_tmp (g, CIRROS_LOGO, "icon", 1024);
+ local = guestfs_int_download_to_tmp (g, CIRROS_LOGO, "png", 1024);
if (!local)
return NOT_FOUND;
@@ -469,8 +469,7 @@ icon_windows_xp (guestfs_h *g, const char *systemroot, size_t *size_r)
if (r == 0)
return NOT_FOUND;
- filename_downloaded = guestfs_int_download_to_tmp (g, filename_case,
- "explorer.exe",
+ filename_downloaded = guestfs_int_download_to_tmp (g, filename_case, "exe",
MAX_WINDOWS_EXPLORER_SIZE);
if (filename_downloaded == NULL)
return NOT_FOUND;
@@ -538,8 +537,7 @@ icon_windows_7 (guestfs_h *g, const char *systemroot, size_t *size_r)
if (win7_explorer[i] == NULL)
return NOT_FOUND;
- filename_downloaded = guestfs_int_download_to_tmp (g, filename_case,
- "explorer.exe",
+ filename_downloaded = guestfs_int_download_to_tmp (g, filename_case, "exe",
MAX_WINDOWS_EXPLORER_SIZE);
if (filename_downloaded == NULL)
return NOT_FOUND;
@@ -592,8 +590,8 @@ icon_windows_8 (guestfs_h *g, size_t *size_r)
if (r == 0)
return NOT_FOUND;
- filename_downloaded = guestfs_int_download_to_tmp (g, filename_case,
- "wlive48x48.png", 8192);
+ filename_downloaded = guestfs_int_download_to_tmp (g, filename_case, "png",
+ 8192);
if (filename_downloaded == NULL)
return NOT_FOUND;
@@ -649,35 +647,31 @@ case_sensitive_path_silently (guestfs_h *g, const char *path)
}
/**
- * Download a guest file to a local temporary file. The file is
- * cached in the temporary directory using C<basename>, and is not
- * downloaded again.
+ * Download a guest file to a local temporary file.
*
* The name of the temporary (downloaded) file is returned. The
* caller must free the pointer, but does I<not> need to delete the
* temporary file. It will be deleted when the handle is closed.
*
+ * The name of the temporary file is randomly generated, but an
+ * extension can be specified using C<extension> (or pass C<NULL> for none).
+ *
* Refuse to download the guest file if it is larger than C<max_size>.
* On this and other errors, C<NULL> is returned.
- *
- * XXX Prior to commit 65cfecb0f5344ec92d3f0d3c2ec0538b6b2726e2 this
- * function used different basenames for each inspection root. After
- * this commit icons probably won't work properly. Needs fixing.
*/
char *
-guestfs_int_download_to_tmp (guestfs_h *g,
- const char *filename,
- const char *basename, uint64_t max_size)
+guestfs_int_download_to_tmp (guestfs_h *g, const char *filename,
+ const char *extension,
+ uint64_t max_size)
{
char *r;
int fd;
char devfd[32];
int64_t size;
- if (asprintf (&r, "%s/%s", g->tmpdir, basename) == -1) {
- perrorf (g, "asprintf");
+ r = guestfs_int_make_temp_path (g, "download", extension);
+ if (r == NULL)
return NULL;
- }
/* Check size of remote file. */
size = guestfs_filesize (g, filename);
--
2.13.2
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