[PATCH V4 0/5] string list functions

[PATCH V4 0/5] string list functions

[Steve Sistare]

Add some handy string list functions for general use, and use them in
live migration functions.  These will also be needed for cpr exec mode.

Changes in V4:
  * added exec migration patch

Steve Sistare (5):
  util: strList_from_string
  qapi: QAPI_LIST_LENGTH
  util: strv_from_strList
  util: strList unit tests
  migration: simplify exec migration functions

 include/monitor/hmp.h     |  1 -
 include/qapi/util.h       | 13 ++++++++
 include/qemu/strList.h    | 30 ++++++++++++++++++
 migration/exec.c          | 58 +++++-----------------------------
 monitor/hmp-cmds.c        | 19 -----------
 net/net-hmp-cmds.c        |  3 +-
 stats/stats-hmp-cmds.c    |  3 +-
 tests/unit/meson.build    |  1 +
 tests/unit/test-strList.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++
 util/meson.build          |  1 +
 util/strList.c            | 38 ++++++++++++++++++++++
 11 files changed, 175 insertions(+), 72 deletions(-)
 create mode 100644 include/qemu/strList.h
 create mode 100644 tests/unit/test-strList.c
 create mode 100644 util/strList.c

-- 
1.8.3.1

[PATCH V4 1/5] util: strList_from_string

[Steve Sistare]

Generalize hmp_split_at_comma() to take any delimiter string, rename
as strList_from_string(), and move it to util/strList.c.

No functional change.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
 include/monitor/hmp.h  |  1 -
 include/qemu/strList.h | 24 ++++++++++++++++++++++++
 monitor/hmp-cmds.c     | 19 -------------------
 net/net-hmp-cmds.c     |  3 ++-
 stats/stats-hmp-cmds.c |  3 ++-
 util/meson.build       |  1 +
 util/strList.c         | 24 ++++++++++++++++++++++++
 7 files changed, 53 insertions(+), 22 deletions(-)
 create mode 100644 include/qemu/strList.h
 create mode 100644 util/strList.c

diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h
index 13f9a2d..2df661e 100644
--- a/include/monitor/hmp.h
+++ b/include/monitor/hmp.h
@@ -19,7 +19,6 @@
 
 bool hmp_handle_error(Monitor *mon, Error *err);
 void hmp_help_cmd(Monitor *mon, const char *name);
-strList *hmp_split_at_comma(const char *str);
 
 void hmp_info_name(Monitor *mon, const QDict *qdict);
 void hmp_info_version(Monitor *mon, const QDict *qdict);
diff --git a/include/qemu/strList.h b/include/qemu/strList.h
new file mode 100644
index 0000000..010237f
--- /dev/null
+++ b/include/qemu/strList.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef QEMU_STR_LIST_H
+#define QEMU_STR_LIST_H
+
+#include "qapi/qapi-builtin-types.h"
+
+/*
+ * Break @in into a strList using the delimiter string @delim.
+ * The delimiter is not included in the result.
+ * Return NULL if @in is NULL or an empty string.
+ * A leading, trailing, or consecutive delimiter produces an
+ * empty string at that position in the output.
+ * All strings are g_strdup'd, and the result can be freed
+ * using qapi_free_strList.
+ */
+strList *strList_from_string(const char *in, const char *delim);
+
+#endif
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index 871898a..66b68a0 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -38,25 +38,6 @@ bool hmp_handle_error(Monitor *mon, Error *err)
     return false;
 }
 
-/*
- * Split @str at comma.
- * A null @str defaults to "".
- */
-strList *hmp_split_at_comma(const char *str)
-{
-    char **split = g_strsplit(str ?: "", ",", -1);
-    strList *res = NULL;
-    strList **tail = &res;
-    int i;
-
-    for (i = 0; split[i]; i++) {
-        QAPI_LIST_APPEND(tail, split[i]);
-    }
-
-    g_free(split);
-    return res;
-}
-
 void hmp_info_name(Monitor *mon, const QDict *qdict)
 {
     NameInfo *info;
diff --git a/net/net-hmp-cmds.c b/net/net-hmp-cmds.c
index 41d326b..e893801 100644
--- a/net/net-hmp-cmds.c
+++ b/net/net-hmp-cmds.c
@@ -26,6 +26,7 @@
 #include "qemu/config-file.h"
 #include "qemu/help_option.h"
 #include "qemu/option.h"
+#include "qemu/strList.h"
 
 void hmp_info_network(Monitor *mon, const QDict *qdict)
 {
@@ -72,7 +73,7 @@ void hmp_announce_self(Monitor *mon, const QDict *qdict)
                                             migrate_announce_params());
 
     qapi_free_strList(params->interfaces);
-    params->interfaces = hmp_split_at_comma(interfaces_str);
+    params->interfaces = strList_from_string(interfaces_str, ",");
     params->has_interfaces = params->interfaces != NULL;
     params->id = g_strdup(id);
     qmp_announce_self(params, NULL);
diff --git a/stats/stats-hmp-cmds.c b/stats/stats-hmp-cmds.c
index 1f91bf8..428c0e6 100644
--- a/stats/stats-hmp-cmds.c
+++ b/stats/stats-hmp-cmds.c
@@ -10,6 +10,7 @@
 #include "monitor/hmp.h"
 #include "monitor/monitor.h"
 #include "qemu/cutils.h"
+#include "qemu/strList.h"
 #include "hw/core/cpu.h"
 #include "qapi/qmp/qdict.h"
 #include "qapi/error.h"
@@ -176,7 +177,7 @@ static StatsFilter *stats_filter(StatsTarget target, const char *names,
             request->provider = provider_idx;
             if (names && !g_str_equal(names, "*")) {
                 request->has_names = true;
-                request->names = hmp_split_at_comma(names);
+                request->names = strList_from_string(names, ",");
             }
             QAPI_LIST_PREPEND(request_list, request);
         }
diff --git a/util/meson.build b/util/meson.build
index af3bf56..e1d1e1f 100644
--- a/util/meson.build
+++ b/util/meson.build
@@ -1,4 +1,5 @@
 util_ss.add(files('osdep.c', 'cutils.c', 'unicode.c', 'qemu-timer-common.c'))
+util_ss.add(files('strList.c'))
 util_ss.add(files('thread-context.c'), numa)
 if not config_host_data.get('CONFIG_ATOMIC64')
   util_ss.add(files('atomic64.c'))
diff --git a/util/strList.c b/util/strList.c
new file mode 100644
index 0000000..7991de3
--- /dev/null
+++ b/util/strList.c
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2023 Red Hat, Inc.
+ * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/strList.h"
+
+strList *strList_from_string(const char *str, const char *delim)
+{
+    g_autofree char **split = g_strsplit(str ?: "", delim, -1);
+    strList *res = NULL;
+    strList **tail = &res;
+    int i;
+
+    for (i = 0; split[i]; i++) {
+        QAPI_LIST_APPEND(tail, split[i]);
+    }
+
+    return res;
+}
-- 
1.8.3.1

[PATCH V4 2/5] qapi: QAPI_LIST_LENGTH

[Steve Sistare]

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/qapi/util.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/qapi/util.h b/include/qapi/util.h
index 81a2b13..e1b8b1d 100644
--- a/include/qapi/util.h
+++ b/include/qapi/util.h
@@ -56,4 +56,17 @@ int parse_qapi_name(const char *name, bool complete);
     (tail) = &(*(tail))->next; \
 } while (0)
 
+/*
+ * For any GenericList @list, return its length.
+ */
+#define QAPI_LIST_LENGTH(list) \
+    ({ \
+        int len = 0; \
+        typeof(list) elem; \
+        for (elem = list; elem != NULL; elem = elem->next) { \
+            len++; \
+        } \
+        len; \
+    })
+
 #endif
-- 
1.8.3.1

[PATCH V4 3/5] util: strv_from_strList

[Steve Sistare]

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/qemu/strList.h |  6 ++++++
 util/strList.c         | 14 ++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/include/qemu/strList.h b/include/qemu/strList.h
index 010237f..4b86aa6 100644
--- a/include/qemu/strList.h
+++ b/include/qemu/strList.h
@@ -21,4 +21,10 @@
  */
 strList *strList_from_string(const char *in, const char *delim);
 
+/*
+ * Produce and return a NULL-terminated array of strings from @args.
+ * The result is g_malloc'd and all strings are g_strdup'd.
+ */
+GStrv strv_from_strList(const strList *args);
+
 #endif
diff --git a/util/strList.c b/util/strList.c
index 7991de3..bad4187 100644
--- a/util/strList.c
+++ b/util/strList.c
@@ -22,3 +22,17 @@ strList *strList_from_string(const char *str, const char *delim)
 
     return res;
 }
+
+GStrv strv_from_strList(const strList *args)
+{
+    const strList *arg;
+    int i = 0;
+    GStrv argv = g_new(char *, QAPI_LIST_LENGTH(args) + 1);
+
+    for (arg = args; arg != NULL; arg = arg->next) {
+        argv[i++] = g_strdup(arg->value);
+    }
+    argv[i] = NULL;
+
+    return argv;
+}
-- 
1.8.3.1

[PATCH V4 4/5] util: strList unit tests

[Steve Sistare]

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 tests/unit/meson.build    |  1 +
 tests/unit/test-strList.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 81 insertions(+)
 create mode 100644 tests/unit/test-strList.c

diff --git a/tests/unit/meson.build b/tests/unit/meson.build
index 69f9c05..113d12e 100644
--- a/tests/unit/meson.build
+++ b/tests/unit/meson.build
@@ -35,6 +35,7 @@ tests = {
   'test-rcu-simpleq': [],
   'test-rcu-tailq': [],
   'test-rcu-slist': [],
+  'test-strList': [],
   'test-qdist': [],
   'test-qht': [],
   'test-qtree': [],
diff --git a/tests/unit/test-strList.c b/tests/unit/test-strList.c
new file mode 100644
index 0000000..49a1cfd
--- /dev/null
+++ b/tests/unit/test-strList.c
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/strList.h"
+
+static strList *make_list(int length)
+{
+    strList *head = 0, *list, **prev = &head;
+
+    while (length--) {
+        list = *prev = g_new0(strList, 1);
+        list->value = g_strdup("aaa");
+        prev = &list->next;
+    }
+    return head;
+}
+
+static void test_length(void)
+{
+    strList *list;
+    int i;
+
+    for (i = 0; i < 5; i++) {
+        list = make_list(i);
+        g_assert_cmpint(i, ==, QAPI_LIST_LENGTH(list));
+        qapi_free_strList(list);
+    }
+}
+
+struct {
+    const char *string;
+    const char *delim;
+    const char *args[5];
+} list_data[] = {
+    { 0, ",", { 0 } },
+    { "", ",", { 0 } },
+    { "a", ",", { "a", 0 } },
+    { "a,b", ",", { "a", "b", 0 } },
+    { "a,b,c", ",", { "a", "b", "c", 0 } },
+    { "first last", " ", { "first", "last", 0 } },
+    { "a:", ":", { "a", "", 0 } },
+    { "a::b", ":", { "a", "", "b", 0 } },
+    { ":", ":", { "", "", 0 } },
+    { ":a", ":", { "", "a", 0 } },
+    { "::a", ":", { "", "", "a", 0 } },
+};
+
+static void test_strv(void)
+{
+    int i, j;
+    const char **expect;
+    strList *list;
+    GStrv args;
+
+    for (i = 0; i < ARRAY_SIZE(list_data); i++) {
+        expect = list_data[i].args;
+        list = strList_from_string(list_data[i].string, list_data[i].delim);
+        args = strv_from_strList(list);
+        qapi_free_strList(list);
+        for (j = 0; expect[j] && args[j]; j++) {
+            g_assert_cmpstr(expect[j], ==, args[j]);
+        }
+        g_assert_null(expect[j]);
+        g_assert_null(args[j]);
+        g_strfreev(args);
+    }
+}
+
+int main(int argc, char **argv)
+{
+    g_test_init(&argc, &argv, NULL);
+    g_test_add_func("/test-string/length", test_length);
+    g_test_add_func("/test-string/strv", test_strv);
+    return g_test_run();
+}
-- 
1.8.3.1

[PATCH V4 5/5] migration: simplify exec migration functions

[Steve Sistare]

Simplify the exec migration code by using list utility functions.

As a side effect, this also fixes a minor memory leak.  On function return,
"g_auto(GStrv) argv" frees argv and each element, which is wrong, because
the function does not own the individual elements.  To compensate, the code
uses g_steal_pointer which NULLs argv and prevents the destructor from
running, but argv is leaked.

Fixes: cbab4face57b ("migration: convert exec backend ...")
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
 migration/exec.c | 58 ++++++++------------------------------------------------
 1 file changed, 8 insertions(+), 50 deletions(-)

diff --git a/migration/exec.c b/migration/exec.c
index 47d2f3b..1312ca7 100644
--- a/migration/exec.c
+++ b/migration/exec.c
@@ -19,12 +19,12 @@
 
 #include "qemu/osdep.h"
 #include "qemu/error-report.h"
+#include "qemu/strList.h"
 #include "channel.h"
 #include "exec.h"
 #include "migration.h"
 #include "io/channel-command.h"
 #include "trace.h"
-#include "qemu/cutils.h"
 
 #ifdef WIN32
 const char *exec_get_cmd_path(void)
@@ -39,51 +39,16 @@ const char *exec_get_cmd_path(void)
 }
 #endif
 
-/* provides the length of strList */
-static int
-str_list_length(strList *list)
-{
-    int len = 0;
-    strList *elem;
-
-    for (elem = list; elem != NULL; elem = elem->next) {
-        len++;
-    }
-
-    return len;
-}
-
-static void
-init_exec_array(strList *command, char **argv, Error **errp)
-{
-    int i = 0;
-    strList *lst;
-
-    for (lst = command; lst; lst = lst->next) {
-        argv[i++] = lst->value;
-    }
-
-    argv[i] = NULL;
-    return;
-}
-
 void exec_start_outgoing_migration(MigrationState *s, strList *command,
                                    Error **errp)
 {
-    QIOChannel *ioc;
-
-    int length = str_list_length(command);
-    g_auto(GStrv) argv = (char **) g_new0(const char *, length + 1);
-
-    init_exec_array(command, argv, errp);
+    QIOChannel *ioc = NULL;
+    g_auto(GStrv) argv = strv_from_strList(command);
+    const char * const *args = (const char * const *) argv;
     g_autofree char *new_command = g_strjoinv(" ", (char **)argv);
 
     trace_migration_exec_outgoing(new_command);
-    ioc = QIO_CHANNEL(
-        qio_channel_command_new_spawn(
-                            (const char * const *) g_steal_pointer(&argv),
-                            O_RDWR,
-                            errp));
+    ioc = QIO_CHANNEL(qio_channel_command_new_spawn(args, O_RDWR, errp));
     if (!ioc) {
         return;
     }
@@ -105,19 +70,12 @@ static gboolean exec_accept_incoming_migration(QIOChannel *ioc,
 void exec_start_incoming_migration(strList *command, Error **errp)
 {
     QIOChannel *ioc;
-
-    int length = str_list_length(command);
-    g_auto(GStrv) argv = (char **) g_new0(const char *, length + 1);
-
-    init_exec_array(command, argv, errp);
+    g_auto(GStrv) argv = strv_from_strList(command);
+    const char * const *args = (const char * const *) argv;
     g_autofree char *new_command = g_strjoinv(" ", (char **)argv);
 
     trace_migration_exec_incoming(new_command);
-    ioc = QIO_CHANNEL(
-        qio_channel_command_new_spawn(
-                            (const char * const *) g_steal_pointer(&argv),
-                            O_RDWR,
-                            errp));
+    ioc = QIO_CHANNEL(qio_channel_command_new_spawn(args, O_RDWR, errp));
     if (!ioc) {
         return;
     }
-- 
1.8.3.1

Re: [PATCH V4 5/5] migration: simplify exec migration functions

[Markus Armbruster]

Het Gala, Peter, or Fabiano, please review.

Steve Sistare <steven.sistare@oracle.com> writes:

> Simplify the exec migration code by using list utility functions.
>
> As a side effect, this also fixes a minor memory leak.  On function return,
> "g_auto(GStrv) argv" frees argv and each element, which is wrong, because
> the function does not own the individual elements.  To compensate, the code
> uses g_steal_pointer which NULLs argv and prevents the destructor from
> running, but argv is leaked.
>
> Fixes: cbab4face57b ("migration: convert exec backend ...")
> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
> ---
>  migration/exec.c | 58 ++++++++------------------------------------------------
>  1 file changed, 8 insertions(+), 50 deletions(-)
>
> diff --git a/migration/exec.c b/migration/exec.c
> index 47d2f3b..1312ca7 100644
> --- a/migration/exec.c
> +++ b/migration/exec.c
> @@ -19,12 +19,12 @@
>  
>  #include "qemu/osdep.h"
>  #include "qemu/error-report.h"
> +#include "qemu/strList.h"
>  #include "channel.h"
>  #include "exec.h"
>  #include "migration.h"
>  #include "io/channel-command.h"
>  #include "trace.h"
> -#include "qemu/cutils.h"
>  
>  #ifdef WIN32
>  const char *exec_get_cmd_path(void)
> @@ -39,51 +39,16 @@ const char *exec_get_cmd_path(void)
>  }
>  #endif
>  
> -/* provides the length of strList */
> -static int
> -str_list_length(strList *list)
> -{
> -    int len = 0;
> -    strList *elem;
> -
> -    for (elem = list; elem != NULL; elem = elem->next) {
> -        len++;
> -    }
> -
> -    return len;
> -}
> -
> -static void
> -init_exec_array(strList *command, char **argv, Error **errp)
> -{
> -    int i = 0;
> -    strList *lst;
> -
> -    for (lst = command; lst; lst = lst->next) {
> -        argv[i++] = lst->value;
> -    }
> -
> -    argv[i] = NULL;
> -    return;
> -}
> -
>  void exec_start_outgoing_migration(MigrationState *s, strList *command,
>                                     Error **errp)
>  {
> -    QIOChannel *ioc;
> -
> -    int length = str_list_length(command);
> -    g_auto(GStrv) argv = (char **) g_new0(const char *, length + 1);
> -
> -    init_exec_array(command, argv, errp);
> +    QIOChannel *ioc = NULL;
> +    g_auto(GStrv) argv = strv_from_strList(command);
> +    const char * const *args = (const char * const *) argv;
>      g_autofree char *new_command = g_strjoinv(" ", (char **)argv);
>  
>      trace_migration_exec_outgoing(new_command);
> -    ioc = QIO_CHANNEL(
> -        qio_channel_command_new_spawn(
> -                            (const char * const *) g_steal_pointer(&argv),
> -                            O_RDWR,
> -                            errp));
> +    ioc = QIO_CHANNEL(qio_channel_command_new_spawn(args, O_RDWR, errp));
>      if (!ioc) {
>          return;
>      }
> @@ -105,19 +70,12 @@ static gboolean exec_accept_incoming_migration(QIOChannel *ioc,
>  void exec_start_incoming_migration(strList *command, Error **errp)
>  {
>      QIOChannel *ioc;
> -
> -    int length = str_list_length(command);
> -    g_auto(GStrv) argv = (char **) g_new0(const char *, length + 1);
> -
> -    init_exec_array(command, argv, errp);
> +    g_auto(GStrv) argv = strv_from_strList(command);
> +    const char * const *args = (const char * const *) argv;
>      g_autofree char *new_command = g_strjoinv(" ", (char **)argv);
>  
>      trace_migration_exec_incoming(new_command);
> -    ioc = QIO_CHANNEL(
> -        qio_channel_command_new_spawn(
> -                            (const char * const *) g_steal_pointer(&argv),
> -                            O_RDWR,
> -                            errp));
> +    ioc = QIO_CHANNEL(qio_channel_command_new_spawn(args, O_RDWR, errp));
>      if (!ioc) {
>          return;
>      }

Re: [PATCH V4 3/5] util: strv_from_strList

[Markus Armbruster]

Steve Sistare <steven.sistare@oracle.com> writes:

> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  include/qemu/strList.h |  6 ++++++
>  util/strList.c         | 14 ++++++++++++++
>  2 files changed, 20 insertions(+)
>
> diff --git a/include/qemu/strList.h b/include/qemu/strList.h
> index 010237f..4b86aa6 100644
> --- a/include/qemu/strList.h
> +++ b/include/qemu/strList.h
> @@ -21,4 +21,10 @@
>   */
>  strList *strList_from_string(const char *in, const char *delim);
>  
> +/*
> + * Produce and return a NULL-terminated array of strings from @args.
> + * The result is g_malloc'd and all strings are g_strdup'd.
> + */
> +GStrv strv_from_strList(const strList *args);
> +
>  #endif
> diff --git a/util/strList.c b/util/strList.c
> index 7991de3..bad4187 100644
> --- a/util/strList.c
> +++ b/util/strList.c
> @@ -22,3 +22,17 @@ strList *strList_from_string(const char *str, const char *delim)
>  
>      return res;
>  }
> +
> +GStrv strv_from_strList(const strList *args)

Suggest to name the argument @list.

> +{
> +    const strList *arg;

Suggest to name this @tail.

> +    int i = 0;
> +    GStrv argv = g_new(char *, QAPI_LIST_LENGTH(args) + 1);
> +
> +    for (arg = args; arg != NULL; arg = arg->next) {
> +        argv[i++] = g_strdup(arg->value);
> +    }
> +    argv[i] = NULL;
> +
> +    return argv;
> +}

Can we use char ** instread of GStrv?  I'd find that clearer.  For what
it's worth, GLib documentation of functions like g_strsplit() doesn't
use the GStrv typedef, either.

Re: [PATCH V4 4/5] util: strList unit tests

[Markus Armbruster]

Steve Sistare <steven.sistare@oracle.com> writes:

> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  tests/unit/meson.build    |  1 +
>  tests/unit/test-strList.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 81 insertions(+)
>  create mode 100644 tests/unit/test-strList.c
>
> diff --git a/tests/unit/meson.build b/tests/unit/meson.build
> index 69f9c05..113d12e 100644
> --- a/tests/unit/meson.build
> +++ b/tests/unit/meson.build
> @@ -35,6 +35,7 @@ tests = {
>    'test-rcu-simpleq': [],
>    'test-rcu-tailq': [],
>    'test-rcu-slist': [],
> +  'test-strList': [],
>    'test-qdist': [],
>    'test-qht': [],
>    'test-qtree': [],
> diff --git a/tests/unit/test-strList.c b/tests/unit/test-strList.c
> new file mode 100644
> index 0000000..49a1cfd
> --- /dev/null
> +++ b/tests/unit/test-strList.c
> @@ -0,0 +1,80 @@
> +/*
> + * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/strList.h"
> +
> +static strList *make_list(int length)
> +{
> +    strList *head = 0, *list, **prev = &head;
> +
> +    while (length--) {
> +        list = *prev = g_new0(strList, 1);
> +        list->value = g_strdup("aaa");
> +        prev = &list->next;
> +    }
> +    return head;
> +}
> +
> +static void test_length(void)
> +{
> +    strList *list;
> +    int i;
> +
> +    for (i = 0; i < 5; i++) {
> +        list = make_list(i);
> +        g_assert_cmpint(i, ==, QAPI_LIST_LENGTH(list));
> +        qapi_free_strList(list);
> +    }
> +}
> +
> +struct {
> +    const char *string;
> +    const char *delim;
> +    const char *args[5];
> +} list_data[] = {
> +    { 0, ",", { 0 } },
> +    { "", ",", { 0 } },
> +    { "a", ",", { "a", 0 } },
> +    { "a,b", ",", { "a", "b", 0 } },
> +    { "a,b,c", ",", { "a", "b", "c", 0 } },
> +    { "first last", " ", { "first", "last", 0 } },
> +    { "a:", ":", { "a", "", 0 } },
> +    { "a::b", ":", { "a", "", "b", 0 } },
> +    { ":", ":", { "", "", 0 } },
> +    { ":a", ":", { "", "a", 0 } },
> +    { "::a", ":", { "", "", "a", 0 } },
> +};

NULL instead of 0, please.

> +
> +static void test_strv(void)
> +{
> +    int i, j;
> +    const char **expect;
> +    strList *list;
> +    GStrv args;

I'd prefer char **argv;

> +
> +    for (i = 0; i < ARRAY_SIZE(list_data); i++) {
> +        expect = list_data[i].args;
> +        list = strList_from_string(list_data[i].string, list_data[i].delim);
> +        args = strv_from_strList(list);
> +        qapi_free_strList(list);
> +        for (j = 0; expect[j] && args[j]; j++) {

Loop stops when either array element is null.  That's wrong, we need to
exhaust both arrays: || instead of &&.

> +            g_assert_cmpstr(expect[j], ==, args[j]);
> +        }
> +        g_assert_null(expect[j]);
> +        g_assert_null(args[j]);
> +        g_strfreev(args);
> +    }
> +}
> +
> +int main(int argc, char **argv)
> +{
> +    g_test_init(&argc, &argv, NULL);
> +    g_test_add_func("/test-string/length", test_length);
> +    g_test_add_func("/test-string/strv", test_strv);
> +    return g_test_run();
> +}

Re: [PATCH V4 2/5] qapi: QAPI_LIST_LENGTH

[Markus Armbruster]

Steve Sistare <steven.sistare@oracle.com> writes:

> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  include/qapi/util.h | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
>
> diff --git a/include/qapi/util.h b/include/qapi/util.h
> index 81a2b13..e1b8b1d 100644
> --- a/include/qapi/util.h
> +++ b/include/qapi/util.h
> @@ -56,4 +56,17 @@ int parse_qapi_name(const char *name, bool complete);
>      (tail) = &(*(tail))->next; \
>  } while (0)
>  
> +/*
> + * For any GenericList @list, return its length.
> + */
> +#define QAPI_LIST_LENGTH(list) \
> +    ({ \
> +        int len = 0; \

size_t

> +        typeof(list) elem; \

Name this @tail, please.

> +        for (elem = list; elem != NULL; elem = elem->next) { \
> +            len++; \
> +        } \
> +        len; \
> +    })
> +
>  #endif

This is a macro instead of a function so users don't have to cast their
FooList * to GenericList *.

The only user outside tests is strv_from_strList().  I'd be tempted to
open-code it there and call it a day.  Or do you have more users in
mind?

If we keep the macro, please align the backslashes like this:

   #define QAPI_LIST_LENGTH(list)                                  \
       ({                                                          \
           int len = 0;                                            \
           typeof(list) elem;                                      \
           for (elem = list; elem != NULL; elem = elem->next) {    \
               len++;                                              \
           }                                                       \
           len;                                                    \
       })

Re: [PATCH V4 1/5] util: strList_from_string

[Markus Armbruster]

I apologize for the lateness of my review.

Steve Sistare <steven.sistare@oracle.com> writes:

> Generalize hmp_split_at_comma() to take any delimiter string, rename
> as strList_from_string(), and move it to util/strList.c.
>
> No functional change.
>
> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>

I can't see an actual use of generalized delimiters outside tests in
this series.  Do you have uses?

> ---
>  include/monitor/hmp.h  |  1 -
>  include/qemu/strList.h | 24 ++++++++++++++++++++++++
>  monitor/hmp-cmds.c     | 19 -------------------
>  net/net-hmp-cmds.c     |  3 ++-
>  stats/stats-hmp-cmds.c |  3 ++-
>  util/meson.build       |  1 +
>  util/strList.c         | 24 ++++++++++++++++++++++++
>  7 files changed, 53 insertions(+), 22 deletions(-)
>  create mode 100644 include/qemu/strList.h
>  create mode 100644 util/strList.c
>
> diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h
> index 13f9a2d..2df661e 100644
> --- a/include/monitor/hmp.h
> +++ b/include/monitor/hmp.h
> @@ -19,7 +19,6 @@
>  
>  bool hmp_handle_error(Monitor *mon, Error *err);
>  void hmp_help_cmd(Monitor *mon, const char *name);
> -strList *hmp_split_at_comma(const char *str);
>  
>  void hmp_info_name(Monitor *mon, const QDict *qdict);
>  void hmp_info_version(Monitor *mon, const QDict *qdict);
> diff --git a/include/qemu/strList.h b/include/qemu/strList.h
> new file mode 100644
> index 0000000..010237f
> --- /dev/null
> +++ b/include/qemu/strList.h
> @@ -0,0 +1,24 @@
> +/*
> + * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#ifndef QEMU_STR_LIST_H
> +#define QEMU_STR_LIST_H
> +
> +#include "qapi/qapi-builtin-types.h"
> +
> +/*
> + * Break @in into a strList using the delimiter string @delim.
> + * The delimiter is not included in the result.
> + * Return NULL if @in is NULL or an empty string.
> + * A leading, trailing, or consecutive delimiter produces an
> + * empty string at that position in the output.
> + * All strings are g_strdup'd, and the result can be freed
> + * using qapi_free_strList.
> + */
> +strList *strList_from_string(const char *in, const char *delim);

The function name no longer tells us explicitly what the function does:
splitting the string.

`> +
> +#endif
> diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
> index 871898a..66b68a0 100644
> --- a/monitor/hmp-cmds.c
> +++ b/monitor/hmp-cmds.c
> @@ -38,25 +38,6 @@ bool hmp_handle_error(Monitor *mon, Error *err)
>      return false;
>  }
>  
> -/*
> - * Split @str at comma.
> - * A null @str defaults to "".
> - */
> -strList *hmp_split_at_comma(const char *str)
> -{
> -    char **split = g_strsplit(str ?: "", ",", -1);
> -    strList *res = NULL;
> -    strList **tail = &res;
> -    int i;
> -
> -    for (i = 0; split[i]; i++) {
> -        QAPI_LIST_APPEND(tail, split[i]);
> -    }
> -
> -    g_free(split);
> -    return res;
> -}
> -
>  void hmp_info_name(Monitor *mon, const QDict *qdict)
>  {
>      NameInfo *info;
> diff --git a/net/net-hmp-cmds.c b/net/net-hmp-cmds.c
> index 41d326b..e893801 100644
> --- a/net/net-hmp-cmds.c
> +++ b/net/net-hmp-cmds.c
> @@ -26,6 +26,7 @@
>  #include "qemu/config-file.h"
>  #include "qemu/help_option.h"
>  #include "qemu/option.h"
> +#include "qemu/strList.h"
>  
>  void hmp_info_network(Monitor *mon, const QDict *qdict)
>  {
> @@ -72,7 +73,7 @@ void hmp_announce_self(Monitor *mon, const QDict *qdict)
>                                              migrate_announce_params());
>  
>      qapi_free_strList(params->interfaces);
> -    params->interfaces = hmp_split_at_comma(interfaces_str);
> +    params->interfaces = strList_from_string(interfaces_str, ",");
>      params->has_interfaces = params->interfaces != NULL;
>      params->id = g_strdup(id);
>      qmp_announce_self(params, NULL);
> diff --git a/stats/stats-hmp-cmds.c b/stats/stats-hmp-cmds.c
> index 1f91bf8..428c0e6 100644
> --- a/stats/stats-hmp-cmds.c
> +++ b/stats/stats-hmp-cmds.c
> @@ -10,6 +10,7 @@
>  #include "monitor/hmp.h"
>  #include "monitor/monitor.h"
>  #include "qemu/cutils.h"
> +#include "qemu/strList.h"
>  #include "hw/core/cpu.h"
>  #include "qapi/qmp/qdict.h"
>  #include "qapi/error.h"
> @@ -176,7 +177,7 @@ static StatsFilter *stats_filter(StatsTarget target, const char *names,
>              request->provider = provider_idx;
>              if (names && !g_str_equal(names, "*")) {
>                  request->has_names = true;
> -                request->names = hmp_split_at_comma(names);
> +                request->names = strList_from_string(names, ",");
>              }
>              QAPI_LIST_PREPEND(request_list, request);
>          }
> diff --git a/util/meson.build b/util/meson.build
> index af3bf56..e1d1e1f 100644
> --- a/util/meson.build
> +++ b/util/meson.build
> @@ -1,4 +1,5 @@
>  util_ss.add(files('osdep.c', 'cutils.c', 'unicode.c', 'qemu-timer-common.c'))
> +util_ss.add(files('strList.c'))
>  util_ss.add(files('thread-context.c'), numa)
>  if not config_host_data.get('CONFIG_ATOMIC64')
>    util_ss.add(files('atomic64.c'))
> diff --git a/util/strList.c b/util/strList.c
> new file mode 100644
> index 0000000..7991de3
> --- /dev/null
> +++ b/util/strList.c
> @@ -0,0 +1,24 @@
> +/*
> + * Copyright (c) 2023 Red Hat, Inc.
> + * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/strList.h"
> +
> +strList *strList_from_string(const char *str, const char *delim)
> +{
> +    g_autofree char **split = g_strsplit(str ?: "", delim, -1);
> +    strList *res = NULL;
> +    strList **tail = &res;
> +    int i;
> +
> +    for (i = 0; split[i]; i++) {
> +        QAPI_LIST_APPEND(tail, split[i]);
> +    }
> +
> +    return res;
> +}

Re: [PATCH V4 5/5] migration: simplify exec migration functions

[Fabiano Rosas]

Steve Sistare <steven.sistare@oracle.com> writes:

> Simplify the exec migration code by using list utility functions.
>
> As a side effect, this also fixes a minor memory leak.  On function return,
> "g_auto(GStrv) argv" frees argv and each element, which is wrong, because
> the function does not own the individual elements.  To compensate, the code
> uses g_steal_pointer which NULLs argv and prevents the destructor from
> running, but argv is leaked.
>
> Fixes: cbab4face57b ("migration: convert exec backend ...")
> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>

Reviewed-by: Fabiano Rosas <farosas@suse.de>

Re: [PATCH V4 5/5] migration: simplify exec migration functions

[Fabiano Rosas]

Fabiano Rosas <farosas@suse.de> writes:

> Steve Sistare <steven.sistare@oracle.com> writes:
>
>> Simplify the exec migration code by using list utility functions.
>>
>> As a side effect, this also fixes a minor memory leak.  On function return,
>> "g_auto(GStrv) argv" frees argv and each element, which is wrong, because
>> the function does not own the individual elements.  To compensate, the code
>> uses g_steal_pointer which NULLs argv and prevents the destructor from
>> running, but argv is leaked.
>>
>> Fixes: cbab4face57b ("migration: convert exec backend ...")
>> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
>
> Reviewed-by: Fabiano Rosas <farosas@suse.de>

You'll have to reintroduce the qemu/cutils.h include:

../migration/exec.c: In function 'exec_get_cmd_path':
../migration/exec.c:37:5: error: implicit declaration of function 'pstrcat'; did you mean 'strcat'? [-Werror=implicit-function-declaration]
   37 |     pstrcat(detected_path, MAX_PATH, "\\cmd.exe");
      |     ^~~~~~~
      |     strcat
../migration/exec.c:37:5: error: nested extern declaration of 'pstrcat' [-Werror=nested-externs]

Re: [PATCH V4 1/5] util: strList_from_string

[Steven Sistare]

On 2/21/2024 8:29 AM, Markus Armbruster wrote:
> I apologize for the lateness of my review.

No problem.  Thanks for the review.

> Steve Sistare <steven.sistare@oracle.com> writes:
> 
>> Generalize hmp_split_at_comma() to take any delimiter string, rename
>> as strList_from_string(), and move it to util/strList.c.
>>
>> No functional change.
>>
>> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
> 
> I can't see an actual use of generalized delimiters outside tests in
> this series.  Do you have uses?

In this series, it is called from hmp_announce_self and stats_filter; 
those were formerly calls to hmp_split_at_comma.

In my live update cpr-exec series, there is an additional call site, with a
space delimiter instead of comma.  Live update V9 is posted but is old and obsolete.  
I will post V10 soon, but I am hoping you can pull this series first, so I can 
whittle down my pending patches and omit these from V10.

>> ---
>>  include/monitor/hmp.h  |  1 -
>>  include/qemu/strList.h | 24 ++++++++++++++++++++++++
>>  monitor/hmp-cmds.c     | 19 -------------------
>>  net/net-hmp-cmds.c     |  3 ++-
>>  stats/stats-hmp-cmds.c |  3 ++-
>>  util/meson.build       |  1 +
>>  util/strList.c         | 24 ++++++++++++++++++++++++
>>  7 files changed, 53 insertions(+), 22 deletions(-)
>>  create mode 100644 include/qemu/strList.h
>>  create mode 100644 util/strList.c
>>
>> diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h
>> index 13f9a2d..2df661e 100644
>> --- a/include/monitor/hmp.h
>> +++ b/include/monitor/hmp.h
>> @@ -19,7 +19,6 @@
>>  
>>  bool hmp_handle_error(Monitor *mon, Error *err);
>>  void hmp_help_cmd(Monitor *mon, const char *name);
>> -strList *hmp_split_at_comma(const char *str);
>>  
>>  void hmp_info_name(Monitor *mon, const QDict *qdict);
>>  void hmp_info_version(Monitor *mon, const QDict *qdict);
>> diff --git a/include/qemu/strList.h b/include/qemu/strList.h
>> new file mode 100644
>> index 0000000..010237f
>> --- /dev/null
>> +++ b/include/qemu/strList.h
>> @@ -0,0 +1,24 @@
>> +/*
>> + * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
>> + * See the COPYING file in the top-level directory.
>> + */
>> +
>> +#ifndef QEMU_STR_LIST_H
>> +#define QEMU_STR_LIST_H
>> +
>> +#include "qapi/qapi-builtin-types.h"
>> +
>> +/*
>> + * Break @in into a strList using the delimiter string @delim.
>> + * The delimiter is not included in the result.
>> + * Return NULL if @in is NULL or an empty string.
>> + * A leading, trailing, or consecutive delimiter produces an
>> + * empty string at that position in the output.
>> + * All strings are g_strdup'd, and the result can be freed
>> + * using qapi_free_strList.
>> + */
>> +strList *strList_from_string(const char *in, const char *delim);
> 
> The function name no longer tells us explicitly what the function does:
> splitting the string.

The first sentence does not say it?
  "Break @in into a strList using the delimiter string @delim"

Would you prefer this?
  "Split string @in into a strList using the delimiter string @delim"

- Steve

>> +#endif
>> diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
>> index 871898a..66b68a0 100644
>> --- a/monitor/hmp-cmds.c
>> +++ b/monitor/hmp-cmds.c
>> @@ -38,25 +38,6 @@ bool hmp_handle_error(Monitor *mon, Error *err)
>>      return false;
>>  }
>>  
>> -/*
>> - * Split @str at comma.
>> - * A null @str defaults to "".
>> - */
>> -strList *hmp_split_at_comma(const char *str)
>> -{
>> -    char **split = g_strsplit(str ?: "", ",", -1);
>> -    strList *res = NULL;
>> -    strList **tail = &res;
>> -    int i;
>> -
>> -    for (i = 0; split[i]; i++) {
>> -        QAPI_LIST_APPEND(tail, split[i]);
>> -    }
>> -
>> -    g_free(split);
>> -    return res;
>> -}
>> -
>>  void hmp_info_name(Monitor *mon, const QDict *qdict)
>>  {
>>      NameInfo *info;
>> diff --git a/net/net-hmp-cmds.c b/net/net-hmp-cmds.c
>> index 41d326b..e893801 100644
>> --- a/net/net-hmp-cmds.c
>> +++ b/net/net-hmp-cmds.c
>> @@ -26,6 +26,7 @@
>>  #include "qemu/config-file.h"
>>  #include "qemu/help_option.h"
>>  #include "qemu/option.h"
>> +#include "qemu/strList.h"
>>  
>>  void hmp_info_network(Monitor *mon, const QDict *qdict)
>>  {
>> @@ -72,7 +73,7 @@ void hmp_announce_self(Monitor *mon, const QDict *qdict)
>>                                              migrate_announce_params());
>>  
>>      qapi_free_strList(params->interfaces);
>> -    params->interfaces = hmp_split_at_comma(interfaces_str);
>> +    params->interfaces = strList_from_string(interfaces_str, ",");
>>      params->has_interfaces = params->interfaces != NULL;
>>      params->id = g_strdup(id);
>>      qmp_announce_self(params, NULL);
>> diff --git a/stats/stats-hmp-cmds.c b/stats/stats-hmp-cmds.c
>> index 1f91bf8..428c0e6 100644
>> --- a/stats/stats-hmp-cmds.c
>> +++ b/stats/stats-hmp-cmds.c
>> @@ -10,6 +10,7 @@
>>  #include "monitor/hmp.h"
>>  #include "monitor/monitor.h"
>>  #include "qemu/cutils.h"
>> +#include "qemu/strList.h"
>>  #include "hw/core/cpu.h"
>>  #include "qapi/qmp/qdict.h"
>>  #include "qapi/error.h"
>> @@ -176,7 +177,7 @@ static StatsFilter *stats_filter(StatsTarget target, const char *names,
>>              request->provider = provider_idx;
>>              if (names && !g_str_equal(names, "*")) {
>>                  request->has_names = true;
>> -                request->names = hmp_split_at_comma(names);
>> +                request->names = strList_from_string(names, ",");
>>              }
>>              QAPI_LIST_PREPEND(request_list, request);
>>          }
>> diff --git a/util/meson.build b/util/meson.build
>> index af3bf56..e1d1e1f 100644
>> --- a/util/meson.build
>> +++ b/util/meson.build
>> @@ -1,4 +1,5 @@
>>  util_ss.add(files('osdep.c', 'cutils.c', 'unicode.c', 'qemu-timer-common.c'))
>> +util_ss.add(files('strList.c'))
>>  util_ss.add(files('thread-context.c'), numa)
>>  if not config_host_data.get('CONFIG_ATOMIC64')
>>    util_ss.add(files('atomic64.c'))
>> diff --git a/util/strList.c b/util/strList.c
>> new file mode 100644
>> index 0000000..7991de3
>> --- /dev/null
>> +++ b/util/strList.c
>> @@ -0,0 +1,24 @@
>> +/*
>> + * Copyright (c) 2023 Red Hat, Inc.
>> + * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
>> + * See the COPYING file in the top-level directory.
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "qemu/strList.h"
>> +
>> +strList *strList_from_string(const char *str, const char *delim)
>> +{
>> +    g_autofree char **split = g_strsplit(str ?: "", delim, -1);
>> +    strList *res = NULL;
>> +    strList **tail = &res;
>> +    int i;
>> +
>> +    for (i = 0; split[i]; i++) {
>> +        QAPI_LIST_APPEND(tail, split[i]);
>> +    }
>> +
>> +    return res;
>> +}
> 

Re: [PATCH V4 2/5] qapi: QAPI_LIST_LENGTH

[Steven Sistare]

On 2/21/2024 8:29 AM, Markus Armbruster wrote:
> Steve Sistare <steven.sistare@oracle.com> writes:
> 
>> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
>> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
>> ---
>>  include/qapi/util.h | 13 +++++++++++++
>>  1 file changed, 13 insertions(+)
>>
>> diff --git a/include/qapi/util.h b/include/qapi/util.h
>> index 81a2b13..e1b8b1d 100644
>> --- a/include/qapi/util.h
>> +++ b/include/qapi/util.h
>> @@ -56,4 +56,17 @@ int parse_qapi_name(const char *name, bool complete);
>>      (tail) = &(*(tail))->next; \
>>  } while (0)
>>  
>> +/*
>> + * For any GenericList @list, return its length.
>> + */
>> +#define QAPI_LIST_LENGTH(list) \
>> +    ({ \
>> +        int len = 0; \
> 
> size_t

ok.

>> +        typeof(list) elem; \
> 
> Name this @tail, please.

ok.

>> +        for (elem = list; elem != NULL; elem = elem->next) { \
>> +            len++; \
>> +        } \
>> +        len; \
>> +    })
>> +
>>  #endif
> 
> This is a macro instead of a function so users don't have to cast their
> FooList * to GenericList *.
> 
> The only user outside tests is strv_from_strList().  I'd be tempted to
> open-code it there and call it a day.  Or do you have more users in
> mind?

That's the only use.  If I make it private, I would still define it as
a static subroutine in util/strList.c, because it simplifies strv_from_strList.
IMO providing a public list length function or macro is pretty basic, but
I am not wedded to it.  Your call.

- Steve

> If we keep the macro, please align the backslashes like this:
> 
>    #define QAPI_LIST_LENGTH(list)                                  \
>        ({                                                          \
>            int len = 0;                                            \
>            typeof(list) elem;                                      \
>            for (elem = list; elem != NULL; elem = elem->next) {    \
>                len++;                                              \
>            }                                                       \
>            len;                                                    \
>        })
> 

Re: [PATCH V4 3/5] util: strv_from_strList

[Steven Sistare]

On 2/21/2024 8:14 AM, Markus Armbruster wrote:
> Steve Sistare <steven.sistare@oracle.com> writes:
> 
>> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
>> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
>> ---
>>  include/qemu/strList.h |  6 ++++++
>>  util/strList.c         | 14 ++++++++++++++
>>  2 files changed, 20 insertions(+)
>>
>> diff --git a/include/qemu/strList.h b/include/qemu/strList.h
>> index 010237f..4b86aa6 100644
>> --- a/include/qemu/strList.h
>> +++ b/include/qemu/strList.h
>> @@ -21,4 +21,10 @@
>>   */
>>  strList *strList_from_string(const char *in, const char *delim);
>>  
>> +/*
>> + * Produce and return a NULL-terminated array of strings from @args.
>> + * The result is g_malloc'd and all strings are g_strdup'd.
>> + */
>> +GStrv strv_from_strList(const strList *args);
>> +
>>  #endif
>> diff --git a/util/strList.c b/util/strList.c
>> index 7991de3..bad4187 100644
>> --- a/util/strList.c
>> +++ b/util/strList.c
>> @@ -22,3 +22,17 @@ strList *strList_from_string(const char *str, const char *delim)
>>  
>>      return res;
>>  }
>> +
>> +GStrv strv_from_strList(const strList *args)
> 
> Suggest to name the argument @list.
> 
>> +{
>> +    const strList *arg;
> 
> Suggest to name this @tail.

ok.

>> +    int i = 0;
>> +    GStrv argv = g_new(char *, QAPI_LIST_LENGTH(args) + 1);
>> +
>> +    for (arg = args; arg != NULL; arg = arg->next) {
>> +        argv[i++] = g_strdup(arg->value);
>> +    }
>> +    argv[i] = NULL;
>> +
>> +    return argv;
>> +}
> 
> Can we use char ** instread of GStrv?  I'd find that clearer.  For what
> it's worth, GLib documentation of functions like g_strsplit() doesn't
> use the GStrv typedef, either.

ok.

- Steve

Re: [PATCH V4 4/5] util: strList unit tests

[Steven Sistare]

On 2/21/2024 8:19 AM, Markus Armbruster wrote:
> Steve Sistare <steven.sistare@oracle.com> writes:
> 
>> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
>> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
>> ---
>>  tests/unit/meson.build    |  1 +
>>  tests/unit/test-strList.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++
>>  2 files changed, 81 insertions(+)
>>  create mode 100644 tests/unit/test-strList.c
>>
>> diff --git a/tests/unit/meson.build b/tests/unit/meson.build
>> index 69f9c05..113d12e 100644
>> --- a/tests/unit/meson.build
>> +++ b/tests/unit/meson.build
>> @@ -35,6 +35,7 @@ tests = {
>>    'test-rcu-simpleq': [],
>>    'test-rcu-tailq': [],
>>    'test-rcu-slist': [],
>> +  'test-strList': [],
>>    'test-qdist': [],
>>    'test-qht': [],
>>    'test-qtree': [],
>> diff --git a/tests/unit/test-strList.c b/tests/unit/test-strList.c
>> new file mode 100644
>> index 0000000..49a1cfd
>> --- /dev/null
>> +++ b/tests/unit/test-strList.c
>> @@ -0,0 +1,80 @@
>> +/*
>> + * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
>> + * See the COPYING file in the top-level directory.
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "qemu/strList.h"
>> +
>> +static strList *make_list(int length)
>> +{
>> +    strList *head = 0, *list, **prev = &head;
>> +
>> +    while (length--) {
>> +        list = *prev = g_new0(strList, 1);
>> +        list->value = g_strdup("aaa");
>> +        prev = &list->next;
>> +    }
>> +    return head;
>> +}
>> +
>> +static void test_length(void)
>> +{
>> +    strList *list;
>> +    int i;
>> +
>> +    for (i = 0; i < 5; i++) {
>> +        list = make_list(i);
>> +        g_assert_cmpint(i, ==, QAPI_LIST_LENGTH(list));
>> +        qapi_free_strList(list);
>> +    }
>> +}
>> +
>> +struct {
>> +    const char *string;
>> +    const char *delim;
>> +    const char *args[5];
>> +} list_data[] = {
>> +    { 0, ",", { 0 } },
>> +    { "", ",", { 0 } },
>> +    { "a", ",", { "a", 0 } },
>> +    { "a,b", ",", { "a", "b", 0 } },
>> +    { "a,b,c", ",", { "a", "b", "c", 0 } },
>> +    { "first last", " ", { "first", "last", 0 } },
>> +    { "a:", ":", { "a", "", 0 } },
>> +    { "a::b", ":", { "a", "", "b", 0 } },
>> +    { ":", ":", { "", "", 0 } },
>> +    { ":a", ":", { "", "a", 0 } },
>> +    { "::a", ":", { "", "", "a", 0 } },
>> +};
> 
> NULL instead of 0, please.

ok.

>> +
>> +static void test_strv(void)
>> +{
>> +    int i, j;
>> +    const char **expect;
>> +    strList *list;
>> +    GStrv args;
> 
> I'd prefer char **argv;

ok.

>> +
>> +    for (i = 0; i < ARRAY_SIZE(list_data); i++) {
>> +        expect = list_data[i].args;
>> +        list = strList_from_string(list_data[i].string, list_data[i].delim);
>> +        args = strv_from_strList(list);
>> +        qapi_free_strList(list);
>> +        for (j = 0; expect[j] && args[j]; j++) {
> 
> Loop stops when either array element is null.  That's wrong, we need to
> exhaust both arrays: || instead of &&.

|| is not safe.  After one array is exhausted, [j] will be out of bounds for
the other.  The g_assert_null calls guarantee the arrays are the same length
and all elements have been compared.

- Steve

>> +            g_assert_cmpstr(expect[j], ==, args[j]);
>> +        }
>> +        g_assert_null(expect[j]);
>> +        g_assert_null(args[j]);
>> +        g_strfreev(args);
>> +    }
>> +}
>> +
>> +int main(int argc, char **argv)
>> +{
>> +    g_test_init(&argc, &argv, NULL);
>> +    g_test_add_func("/test-string/length", test_length);
>> +    g_test_add_func("/test-string/strv", test_strv);
>> +    return g_test_run();
>> +}
> 

Re: [PATCH V4 5/5] migration: simplify exec migration functions

[Steven Sistare]

On 2/21/2024 10:54 AM, Fabiano Rosas wrote:
> Fabiano Rosas <farosas@suse.de> writes:
> 
>> Steve Sistare <steven.sistare@oracle.com> writes:
>>
>>> Simplify the exec migration code by using list utility functions.
>>>
>>> As a side effect, this also fixes a minor memory leak.  On function return,
>>> "g_auto(GStrv) argv" frees argv and each element, which is wrong, because
>>> the function does not own the individual elements.  To compensate, the code
>>> uses g_steal_pointer which NULLs argv and prevents the destructor from
>>> running, but argv is leaked.
>>>
>>> Fixes: cbab4face57b ("migration: convert exec backend ...")
>>> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
>>
>> Reviewed-by: Fabiano Rosas <farosas@suse.de>
> 
> You'll have to reintroduce the qemu/cutils.h include:
> 
> ../migration/exec.c: In function 'exec_get_cmd_path':
> ../migration/exec.c:37:5: error: implicit declaration of function 'pstrcat'; did you mean 'strcat'? [-Werror=implicit-function-declaration]
>    37 |     pstrcat(detected_path, MAX_PATH, "\\cmd.exe");
>       |     ^~~~~~~
>       |     strcat
> ../migration/exec.c:37:5: error: nested extern declaration of 'pstrcat' [-Werror=nested-externs]

Thanks, I will rebase to the tip and verify all is well before I post V5.

- Steve

Re: [PATCH V4 1/5] util: strList_from_string

[Steven Sistare]

On 2/21/2024 12:01 PM, Steven Sistare wrote:
> On 2/21/2024 8:29 AM, Markus Armbruster wrote:
>> I apologize for the lateness of my review.
> 
> No problem.  Thanks for the review.
> 
>> Steve Sistare <steven.sistare@oracle.com> writes:
>>
>>> Generalize hmp_split_at_comma() to take any delimiter string, rename
>>> as strList_from_string(), and move it to util/strList.c.
>>>
>>> No functional change.
>>>
>>> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
>>
>> I can't see an actual use of generalized delimiters outside tests in
>> this series.  Do you have uses?
> 
> In this series, it is called from hmp_announce_self and stats_filter; 
> those were formerly calls to hmp_split_at_comma.
> 
> In my live update cpr-exec series, there is an additional call site, with a
> space delimiter instead of comma.  Live update V9 is posted but is old and obsolete.  
> I will post V10 soon, but I am hoping you can pull this series first, so I can 
> whittle down my pending patches and omit these from V10.
> 
>>> ---
>>>  include/monitor/hmp.h  |  1 -
>>>  include/qemu/strList.h | 24 ++++++++++++++++++++++++
>>>  monitor/hmp-cmds.c     | 19 -------------------
>>>  net/net-hmp-cmds.c     |  3 ++-
>>>  stats/stats-hmp-cmds.c |  3 ++-
>>>  util/meson.build       |  1 +
>>>  util/strList.c         | 24 ++++++++++++++++++++++++
>>>  7 files changed, 53 insertions(+), 22 deletions(-)
>>>  create mode 100644 include/qemu/strList.h
>>>  create mode 100644 util/strList.c
>>>
>>> diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h
>>> index 13f9a2d..2df661e 100644
>>> --- a/include/monitor/hmp.h
>>> +++ b/include/monitor/hmp.h
>>> @@ -19,7 +19,6 @@
>>>  
>>>  bool hmp_handle_error(Monitor *mon, Error *err);
>>>  void hmp_help_cmd(Monitor *mon, const char *name);
>>> -strList *hmp_split_at_comma(const char *str);
>>>  
>>>  void hmp_info_name(Monitor *mon, const QDict *qdict);
>>>  void hmp_info_version(Monitor *mon, const QDict *qdict);
>>> diff --git a/include/qemu/strList.h b/include/qemu/strList.h
>>> new file mode 100644
>>> index 0000000..010237f
>>> --- /dev/null
>>> +++ b/include/qemu/strList.h
>>> @@ -0,0 +1,24 @@
>>> +/*
>>> + * Copyright (c) 2022 - 2024 Oracle and/or its affiliates.
>>> + *
>>> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
>>> + * See the COPYING file in the top-level directory.
>>> + */
>>> +
>>> +#ifndef QEMU_STR_LIST_H
>>> +#define QEMU_STR_LIST_H
>>> +
>>> +#include "qapi/qapi-builtin-types.h"
>>> +
>>> +/*
>>> + * Break @in into a strList using the delimiter string @delim.
>>> + * The delimiter is not included in the result.
>>> + * Return NULL if @in is NULL or an empty string.
>>> + * A leading, trailing, or consecutive delimiter produces an
>>> + * empty string at that position in the output.
>>> + * All strings are g_strdup'd, and the result can be freed
>>> + * using qapi_free_strList.
>>> + */
>>> +strList *strList_from_string(const char *in, const char *delim);
>>
>> The function name no longer tells us explicitly what the function does:
>> splitting the string.
> 
> The first sentence does not say it?
>   "Break @in into a strList using the delimiter string @delim"
> 
> Would you prefer this?
>   "Split string @in into a strList using the delimiter string @delim"

Sorry, I read your comment too quickly.  You want a different function name.
I propose:
  strList *str_split(const char *str, const char *delim);

- Steve