From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52669) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aTFot-0002KP-Sw for qemu-devel@nongnu.org; Tue, 09 Feb 2016 16:27:37 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aTFol-0004Rx-Ec for qemu-devel@nongnu.org; Tue, 09 Feb 2016 16:27:32 -0500 Received: from resqmta-po-10v.sys.comcast.net ([96.114.154.169]:44439) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aTFol-0004Rq-6b for qemu-devel@nongnu.org; Tue, 09 Feb 2016 16:27:27 -0500 From: Eric Blake Date: Tue, 9 Feb 2016 14:27:16 -0700 Message-Id: <1455053236-22735-1-git-send-email-eblake@redhat.com> Subject: [Qemu-devel] [PATCH v3] qga: Support enum names in guest-file-seek List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Michael Roth Magic constants are a pain to use, especially when we run the risk that our choice of '1' for QGA_SEEK_CUR might differ from the host or guest's choice of SEEK_CUR. Better is to use an enum value, via a qapi alternate type for back-compatibility. With this, {"command":"guest-file-seek", "arguments":{"handle":1, "offset":0, "whence":"cur"}} becomes a synonym for the older {"command":"guest-file-seek", "arguments":{"handle":1, "offset":0, "whence":1}} Signed-off-by: Eric Blake --- v2: rebase on top of qapi work --- v3: rebase to latest v2 was here: https://lists.gnu.org/archive/html/qemu-devel/2015-12/msg03565.html v1 was here: https://lists.gnu.org/archive/html/qemu-devel/2015-11/msg05730.html qga/guest-agent-core.h | 9 ++------- qga/commands-posix.c | 19 ++++++------------- qga/commands-win32.c | 19 ++++++------------- qga/commands.c | 21 +++++++++++++++++++++ tests/test-qga.c | 9 ++++----- qga/qapi-schema.json | 33 +++++++++++++++++++++++++++++++-- 6 files changed, 70 insertions(+), 40 deletions(-) diff --git a/qga/guest-agent-core.h b/qga/guest-agent-core.h index 238dc6b..0a49516 100644 --- a/qga/guest-agent-core.h +++ b/qga/guest-agent-core.h @@ -12,16 +12,10 @@ */ #include "qapi/qmp/dispatch.h" #include "qemu-common.h" +#include "qga-qmp-commands.h" #define QGA_READ_COUNT_DEFAULT 4096 -/* Mapping of whence codes used by guest-file-seek. */ -enum { - QGA_SEEK_SET = 0, - QGA_SEEK_CUR = 1, - QGA_SEEK_END = 2, -}; - typedef struct GAState GAState; typedef struct GACommandState GACommandState; extern GAState *ga_state; @@ -44,6 +38,7 @@ void ga_set_frozen(GAState *s); void ga_unset_frozen(GAState *s); const char *ga_fsfreeze_hook(GAState *s); int64_t ga_get_fd_handle(GAState *s, Error **errp); +int ga_parse_whence(GuestFileWhence *whence, Error **errp); #ifndef _WIN32 void reopen_fd_to_null(int fd); diff --git a/qga/commands-posix.c b/qga/commands-posix.c index 9589b2d..9f51fae 100644 --- a/qga/commands-posix.c +++ b/qga/commands-posix.c @@ -550,31 +550,24 @@ GuestFileWrite *qmp_guest_file_write(int64_t handle, const char *buf_b64, } struct GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset, - int64_t whence_code, Error **errp) + GuestFileWhence *whence_code, + Error **errp) { GuestFileHandle *gfh = guest_file_handle_find(handle, errp); GuestFileSeek *seek_data = NULL; FILE *fh; int ret; int whence; + Error *err = NULL; if (!gfh) { return NULL; } /* We stupidly exposed 'whence':'int' in our qapi */ - switch (whence_code) { - case QGA_SEEK_SET: - whence = SEEK_SET; - break; - case QGA_SEEK_CUR: - whence = SEEK_CUR; - break; - case QGA_SEEK_END: - whence = SEEK_END; - break; - default: - error_setg(errp, "invalid whence code %"PRId64, whence_code); + whence = ga_parse_whence(whence_code, &err); + if (err) { + error_propagate(errp, err); return NULL; } diff --git a/qga/commands-win32.c b/qga/commands-win32.c index cf0757c..2799f5f 100644 --- a/qga/commands-win32.c +++ b/qga/commands-win32.c @@ -385,7 +385,8 @@ done: } GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset, - int64_t whence_code, Error **errp) + GuestFileWhence *whence_code, + Error **errp) { GuestFileHandle *gfh; GuestFileSeek *seek_data; @@ -394,6 +395,7 @@ GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset, off_pos.QuadPart = offset; BOOL res; int whence; + Error *err = NULL; gfh = guest_file_handle_find(handle, errp); if (!gfh) { @@ -401,18 +403,9 @@ GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset, } /* We stupidly exposed 'whence':'int' in our qapi */ - switch (whence_code) { - case QGA_SEEK_SET: - whence = SEEK_SET; - break; - case QGA_SEEK_CUR: - whence = SEEK_CUR; - break; - case QGA_SEEK_END: - whence = SEEK_END; - break; - default: - error_setg(errp, "invalid whence code %"PRId64, whence_code); + whence = ga_parse_whence(whence_code, &err); + if (err) { + error_propagate(errp, err); return NULL; } diff --git a/qga/commands.c b/qga/commands.c index 5b56786..e091ee1 100644 --- a/qga/commands.c +++ b/qga/commands.c @@ -473,3 +473,24 @@ done: return ge; } + +/* Convert GuestFileWhence (either a raw integer or an enum value) into + * the guest's SEEK_ constants. */ +int ga_parse_whence(GuestFileWhence *whence, Error **errp) +{ + /* Exploit the fact that we picked values to match QGA_SEEK_*. */ + if (whence->type == QTYPE_QSTRING) { + whence->type = QTYPE_QINT; + whence->u.value = whence->u.name; + } + switch (whence->u.value) { + case QGA_SEEK_SET: + return SEEK_SET; + case QGA_SEEK_CUR: + return SEEK_CUR; + case QGA_SEEK_END: + return SEEK_END; + } + error_setg(errp, "invalid whence code %"PRId64, whence->u.value); + return -1; +} diff --git a/tests/test-qga.c b/tests/test-qga.c index 993b007..4d7542e 100644 --- a/tests/test-qga.c +++ b/tests/test-qga.c @@ -7,7 +7,6 @@ #include "libqtest.h" #include "config-host.h" -#include "qga/guest-agent-core.h" typedef struct { char *test_dir; @@ -451,8 +450,8 @@ static void test_qga_file_ops(gconstpointer fix) /* seek */ cmd = g_strdup_printf("{'execute': 'guest-file-seek'," " 'arguments': { 'handle': %" PRId64 ", " - " 'offset': %d, 'whence': %d } }", - id, 6, QGA_SEEK_SET); + " 'offset': %d, 'whence': '%s' } }", + id, 6, "set"); ret = qmp_fd(fixture->fd, cmd); qmp_assert_no_error(ret); val = qdict_get_qdict(ret, "return"); @@ -544,8 +543,8 @@ static void test_qga_file_write_read(gconstpointer fix) /* seek to 0 */ cmd = g_strdup_printf("{'execute': 'guest-file-seek'," " 'arguments': { 'handle': %" PRId64 ", " - " 'offset': %d, 'whence': %d } }", - id, 0, QGA_SEEK_SET); + " 'offset': %d, 'whence': '%s' } }", + id, 0, "set"); ret = qmp_fd(fixture->fd, cmd); qmp_assert_no_error(ret); val = qdict_get_qdict(ret, "return"); diff --git a/qga/qapi-schema.json b/qga/qapi-schema.json index 01c9ee4..c21f308 100644 --- a/qga/qapi-schema.json +++ b/qga/qapi-schema.json @@ -314,6 +314,34 @@ 'data': { 'position': 'int', 'eof': 'bool' } } ## +# @QGASeek: +# +# Symbolic names for use in @guest-file-seek +# +# @set: Set to the specified offset (same effect as 'whence':0) +# @cur: Add offset to the current location (same effect as 'whence':1) +# @end: Add offset to the end of the file (same effect as 'whence':2) +# +# Since: 2.6 +## +{ 'enum': 'QGASeek', 'data': [ 'set', 'cur', 'end' ] } + +## +# @GuestFileWhence: +# +# Controls the meaning of offset to @guest-file-seek. +# +# @value: Integral value (0 for set, 1 for cur, 2 for end), available +# for historical reasons, and might differ from the host's or +# guest's SEEK_* values (since: 0.15) +# @name: Symbolic name, and preferred interface +# +# Since: 2.6 +## +{ 'alternate': 'GuestFileWhence', + 'data': { 'value': 'int', 'name': 'QGASeek' } } + +## # @guest-file-seek: # # Seek to a position in the file, as with fseek(), and return the @@ -324,14 +352,15 @@ # # @offset: bytes to skip over in the file stream # -# @whence: 0 for SEEK_SET, 1 for SEEK_CUR, or 2 for SEEK_END +# @whence: Symbolic or numeric code for interpreting offset # # Returns: @GuestFileSeek on success. # # Since: 0.15.0 ## { 'command': 'guest-file-seek', - 'data': { 'handle': 'int', 'offset': 'int', 'whence': 'int' }, + 'data': { 'handle': 'int', 'offset': 'int', + 'whence': 'GuestFileWhence' }, 'returns': 'GuestFileSeek' } ## -- 2.5.0