diff options
author | Yuri Pudgorodskiy <yur@virtuozzo.com> | 2015-10-13 18:41:23 +0300 |
---|---|---|
committer | Michael Roth <mdroth@linux.vnet.ibm.com> | 2015-10-19 18:31:54 -0500 |
commit | a1853dca74362551ec1434b2e15acfcdd53caa99 (patch) | |
tree | 2a8ca7e59cfda1867ef3b77ca8f10c70e00848e8 | |
parent | f74df9bfce6d133fc64d6b878327849ed2b89b4b (diff) | |
download | hqemu-a1853dca74362551ec1434b2e15acfcdd53caa99.zip hqemu-a1853dca74362551ec1434b2e15acfcdd53caa99.tar.gz |
qga: guest-exec simple stdin/stdout/stderr redirection
Implemented with base64-encoded strings in qga json protocol.
Glib portable GIOChannel is used for data I/O.
Optinal stdin parameter of guest-exec command is now used as
stdin content for spawned subprocess.
If capture-output bool flag is specified, guest-exec redirects out/err
file descriptiors internally to pipes and collects subprocess
output.
Guest-exe-status is modified to return this collected data to requestor
in base64 encoding.
Signed-off-by: Yuri Pudgorodskiy <yur@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
* switch from 'struct GuestIOExecData' to 'GuestIOExecData'
* s/TRUE/true/g, s/FALSE/false/g for gboolean return values
* s/inp_data/input_data/
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
-rw-r--r-- | qga/commands.c | 189 | ||||
-rw-r--r-- | qga/qapi-schema.json | 7 |
2 files changed, 187 insertions, 9 deletions
diff --git a/qga/commands.c b/qga/commands.c index 68e8cfa..0f80ce6 100644 --- a/qga/commands.c +++ b/qga/commands.c @@ -15,6 +15,11 @@ #include "qga-qmp-commands.h" #include "qapi/qmp/qerror.h" +/* Maximum captured guest-exec out_data/err_data - 16MB */ +#define GUEST_EXEC_MAX_OUTPUT (16*1024*1024) +/* Allocation and I/O buffer for reading guest-exec out_data/err_data - 4KB */ +#define GUEST_EXEC_IO_SIZE (4*1024) + /* Note: in some situations, like with the fsfreeze, logging may be * temporarilly disabled. if it is necessary that a command be able * to log for accounting purposes, check ga_logging_enabled() beforehand, @@ -71,11 +76,25 @@ struct GuestAgentInfo *qmp_guest_info(Error **errp) return info; } +struct GuestExecIOData { + guchar *data; + gsize size; + gsize length; + gint closed; + bool truncated; + const char *name; +}; +typedef struct GuestExecIOData GuestExecIOData; + struct GuestExecInfo { GPid pid; int64_t pid_numeric; gint status; - bool finished; + bool has_output; + gint finished; + GuestExecIOData in; + GuestExecIOData out; + GuestExecIOData err; QTAILQ_ENTRY(GuestExecInfo) next; }; typedef struct GuestExecInfo GuestExecInfo; @@ -134,9 +153,18 @@ GuestExecStatus *qmp_guest_exec_status(int64_t pid, Error **err) } ges = g_new0(GuestExecStatus, 1); - ges->exited = gei->finished; - if (gei->finished) { + bool finished = g_atomic_int_get(&gei->finished); + + /* need to wait till output channels are closed + * to be sure we captured all output at this point */ + if (gei->has_output) { + finished = finished && g_atomic_int_get(&gei->out.closed); + finished = finished && g_atomic_int_get(&gei->err.closed); + } + + ges->exited = finished; + if (finished) { /* Glib has no portable way to parse exit status. * On UNIX, we can get either exit code from normal termination * or signal number. @@ -171,6 +199,20 @@ GuestExecStatus *qmp_guest_exec_status(int64_t pid, Error **err) ges->signal = WTERMSIG(gei->status); } #endif + if (gei->out.length > 0) { + ges->has_out_data = true; + ges->out_data = g_base64_encode(gei->out.data, gei->out.length); + g_free(gei->out.data); + ges->has_out_truncated = gei->out.truncated; + } + + if (gei->err.length > 0) { + ges->has_err_data = true; + ges->err_data = g_base64_encode(gei->err.data, gei->err.length); + g_free(gei->err.data); + ges->has_err_truncated = gei->err.truncated; + } + QTAILQ_REMOVE(&guest_exec_state.processes, gei, next); g_free(gei); } @@ -241,6 +283,98 @@ static void guest_exec_task_setup(gpointer data) #endif } +static gboolean guest_exec_input_watch(GIOChannel *ch, + GIOCondition cond, gpointer p_) +{ + GuestExecIOData *p = (GuestExecIOData *)p_; + gsize bytes_written = 0; + GIOStatus status; + GError *gerr = NULL; + + /* nothing left to write */ + if (p->size == p->length) { + goto done; + } + + status = g_io_channel_write_chars(ch, (gchar *)p->data + p->length, + p->size - p->length, &bytes_written, &gerr); + + /* can be not 0 even if not G_IO_STATUS_NORMAL */ + if (bytes_written != 0) { + p->length += bytes_written; + } + + /* continue write, our callback will be called again */ + if (status == G_IO_STATUS_NORMAL || status == G_IO_STATUS_AGAIN) { + return true; + } + + if (gerr) { + g_warning("qga: i/o error writing to input_data channel: %s", + gerr->message); + g_error_free(gerr); + } + +done: + g_io_channel_shutdown(ch, true, NULL); + g_io_channel_unref(ch); + g_atomic_int_set(&p->closed, 1); + g_free(p->data); + + return false; +} + +static gboolean guest_exec_output_watch(GIOChannel *ch, + GIOCondition cond, gpointer p_) +{ + GuestExecIOData *p = (GuestExecIOData *)p_; + gsize bytes_read; + GIOStatus gstatus; + + if (cond == G_IO_HUP || cond == G_IO_ERR) { + goto close; + } + + if (p->size == p->length) { + gpointer t = NULL; + if (!p->truncated && p->size < GUEST_EXEC_MAX_OUTPUT) { + t = g_try_realloc(p->data, p->size + GUEST_EXEC_IO_SIZE); + } + if (t == NULL) { + /* ignore truncated output */ + gchar buf[GUEST_EXEC_IO_SIZE]; + + p->truncated = true; + gstatus = g_io_channel_read_chars(ch, buf, sizeof(buf), + &bytes_read, NULL); + if (gstatus == G_IO_STATUS_EOF || gstatus == G_IO_STATUS_ERROR) { + goto close; + } + + return true; + } + p->size += GUEST_EXEC_IO_SIZE; + p->data = t; + } + + /* Calling read API once. + * On next available data our callback will be called again */ + gstatus = g_io_channel_read_chars(ch, (gchar *)p->data + p->length, + p->size - p->length, &bytes_read, NULL); + if (gstatus == G_IO_STATUS_EOF || gstatus == G_IO_STATUS_ERROR) { + goto close; + } + + p->length += bytes_read; + + return true; + +close: + g_io_channel_unref(ch); + g_atomic_int_set(&p->closed, 1); + return false; +} + GuestExec *qmp_guest_exec(const char *path, bool has_arg, strList *arg, bool has_env, strList *env, @@ -255,6 +389,10 @@ GuestExec *qmp_guest_exec(const char *path, strList arglist; gboolean ret; GError *gerr = NULL; + gint in_fd, out_fd, err_fd; + GIOChannel *in_ch, *out_ch, *err_ch; + GSpawnFlags flags; + bool has_output = (has_capture_output && capture_output); arglist.value = (char *)path; arglist.next = has_arg ? arg : NULL; @@ -262,11 +400,14 @@ GuestExec *qmp_guest_exec(const char *path, argv = guest_exec_get_args(&arglist, true); envp = guest_exec_get_args(has_env ? env : NULL, false); - ret = g_spawn_async_with_pipes(NULL, argv, envp, - G_SPAWN_SEARCH_PATH | - G_SPAWN_DO_NOT_REAP_CHILD | - G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL, - guest_exec_task_setup, NULL, &pid, NULL, NULL, NULL, &gerr); + flags = G_SPAWN_SEARCH_PATH | G_SPAWN_DO_NOT_REAP_CHILD; + if (!has_output) { + flags |= G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL; + } + + ret = g_spawn_async_with_pipes(NULL, argv, envp, flags, + guest_exec_task_setup, NULL, &pid, has_input_data ? &in_fd : NULL, + has_output ? &out_fd : NULL, has_output ? &err_fd : NULL, &gerr); if (!ret) { error_setg(err, QERR_QGA_COMMAND_FAILED, gerr->message); g_error_free(gerr); @@ -277,8 +418,40 @@ GuestExec *qmp_guest_exec(const char *path, ge->pid = gpid_to_int64(pid); gei = guest_exec_info_add(pid); + gei->has_output = has_output; g_child_watch_add(pid, guest_exec_child_watch, gei); + if (has_input_data) { + gei->in.data = g_base64_decode(input_data, &gei->in.size); +#ifdef G_OS_WIN32 + in_ch = g_io_channel_win32_new_fd(in_fd); +#else + in_ch = g_io_channel_unix_new(in_fd); +#endif + g_io_channel_set_encoding(in_ch, NULL, NULL); + g_io_channel_set_buffered(in_ch, false); + g_io_channel_set_flags(in_ch, G_IO_FLAG_NONBLOCK, NULL); + g_io_add_watch(in_ch, G_IO_OUT, guest_exec_input_watch, &gei->in); + } + + if (has_output) { +#ifdef G_OS_WIN32 + out_ch = g_io_channel_win32_new_fd(out_fd); + err_ch = g_io_channel_win32_new_fd(err_fd); +#else + out_ch = g_io_channel_unix_new(out_fd); + err_ch = g_io_channel_unix_new(err_fd); +#endif + g_io_channel_set_encoding(out_ch, NULL, NULL); + g_io_channel_set_encoding(err_ch, NULL, NULL); + g_io_channel_set_buffered(out_ch, false); + g_io_channel_set_buffered(err_ch, false); + g_io_add_watch(out_ch, G_IO_IN | G_IO_HUP, + guest_exec_output_watch, &gei->out); + g_io_add_watch(err_ch, G_IO_IN | G_IO_HUP, + guest_exec_output_watch, &gei->err); + } + done: g_free(argv); g_free(envp); diff --git a/qga/qapi-schema.json b/qga/qapi-schema.json index 4900b5e..78362e0 100644 --- a/qga/qapi-schema.json +++ b/qga/qapi-schema.json @@ -941,12 +941,17 @@ # @err-data: #optional base64-encoded stderr of the process # Note: @out-data and @err-data are present only # if 'capture-output' was specified for 'guest-exec' +# @out-truncated: #optional true if stdout was not fully captured +# due to size limitation. +# @err-truncated: #optional true if stderr was not fully captured +# due to size limitation. # # Since: 2.5 ## { 'struct': 'GuestExecStatus', 'data': { 'exited': 'bool', '*exitcode': 'int', '*signal': 'int', - '*out-data': 'str', '*err-data': 'str' }} + '*out-data': 'str', '*err-data': 'str', + '*out-truncated': 'bool', '*err-truncated': 'bool' }} ## # @guest-exec-status # |