From 4b3bbc27a6554471969347a1f0ddd70cd80e2b0b Mon Sep 17 00:00:00 2001

From: Markus Armbruster <armbru@redhat.com>

Date: Mon, 18 Jun 2018 08:43:16 +0200

Subject: [PATCH 09/54] qobject: Move block-specific qdict code to

 block-qdict.c

RH-Author: Markus Armbruster <armbru@redhat.com>

Message-id: <20180618084330.30009-10-armbru@redhat.com>

Patchwork-id: 80722

O-Subject: [RHEL-7.6 qemu-kvm-rhev PATCH 09/23] qobject: Move block-specific qdict code to block-qdict.c

Bugzilla: 1557995

RH-Acked-by: Max Reitz <mreitz@redhat.com>

RH-Acked-by: Jeffrey Cody <jcody@redhat.com>

RH-Acked-by: Kevin Wolf <kwolf@redhat.com>

Pure code motion, except for two brace placements and a comment

tweaked to appease checkpatch.

Signed-off-by: Markus Armbruster <armbru@redhat.com>

Reviewed-by: Kevin Wolf <kwolf@redhat.com>

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

(cherry picked from commit 0bcc8e5bd8d6fd6e5cb6462054f7cfa45b282f9a)

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 MAINTAINERS               |   2 +

 qobject/Makefile.objs     |   1 +

 qobject/block-qdict.c     | 640 ++++++++++++++++++++++++++++++++++++++++++++

 qobject/qdict.c           | 629 --------------------------------------------

 tests/Makefile.include    |   4 +

 tests/check-block-qdict.c | 655 ++++++++++++++++++++++++++++++++++++++++++++++

 tests/check-qdict.c       | 642 ---------------------------------------------

 7 files changed, 1302 insertions(+), 1271 deletions(-)

 create mode 100644 qobject/block-qdict.c

 create mode 100644 tests/check-block-qdict.c

diff --git a/MAINTAINERS b/MAINTAINERS

index 24b7016..ad5edc8 100644

--- a/MAINTAINERS

+++ b/MAINTAINERS

@@ -1339,6 +1339,8 @@ F: qemu-img*

 F: qemu-io*

 F: tests/qemu-iotests/

 F: util/qemu-progress.c

+F: qobject/block-qdict.c

+F: test/check-block-qdict.c

 T: git git://repo.or.cz/qemu/kevin.git block

 Block I/O path

diff --git a/qobject/Makefile.objs b/qobject/Makefile.objs

index 002d258..7b12c9c 100644

--- a/qobject/Makefile.objs

+++ b/qobject/Makefile.objs

@@ -1,2 +1,3 @@

 util-obj-y = qnull.o qnum.o qstring.o qdict.o qlist.o qbool.o qlit.o

 util-obj-y += qjson.o qobject.o json-lexer.o json-streamer.o json-parser.o

+util-obj-y += block-qdict.o

diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c

new file mode 100644

index 0000000..fb92010

--- /dev/null

+++ b/qobject/block-qdict.c

@@ -0,0 +1,640 @@

+/*

+ * Special QDict functions used by the block layer

+ *

+ * Copyright (c) 2013-2018 Red Hat, Inc.

+ *

+ * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.

+ * See the COPYING.LIB file in the top-level directory.

+ */

+

+#include "qemu/osdep.h"

+#include "block/qdict.h"

+#include "qapi/qmp/qlist.h"

+#include "qemu/cutils.h"

+#include "qapi/error.h"

+

+/**

+ * qdict_copy_default(): If no entry mapped by 'key' exists in 'dst' yet, the

+ * value of 'key' in 'src' is copied there (and the refcount increased

+ * accordingly).

+ */

+void qdict_copy_default(QDict *dst, QDict *src, const char *key)

+{

+    QObject *val;

+

+    if (qdict_haskey(dst, key)) {

+        return;

+    }

+

+    val = qdict_get(src, key);

+    if (val) {

+        qdict_put_obj(dst, key, qobject_ref(val));

+    }

+}

+

+/**

+ * qdict_set_default_str(): If no entry mapped by 'key' exists in 'dst' yet, a

+ * new QString initialised by 'val' is put there.

+ */

+void qdict_set_default_str(QDict *dst, const char *key, const char *val)

+{

+    if (qdict_haskey(dst, key)) {

+        return;

+    }

+

+    qdict_put_str(dst, key, val);

+}

+

+static void qdict_flatten_qdict(QDict *qdict, QDict *target,

+                                const char *prefix);

+

+static void qdict_flatten_qlist(QList *qlist, QDict *target, const char *prefix)

+{

+    QObject *value;

+    const QListEntry *entry;

+    char *new_key;

+    int i;

+

+    /* This function is never called with prefix == NULL, i.e., it is always

+     * called from within qdict_flatten_q(list|dict)(). Therefore, it does not

+     * need to remove list entries during the iteration (the whole list will be

+     * deleted eventually anyway from qdict_flatten_qdict()). */

+    assert(prefix);

+

+    entry = qlist_first(qlist);

+

+    for (i = 0; entry; entry = qlist_next(entry), i++) {

+        value = qlist_entry_obj(entry);

+        new_key = g_strdup_printf("%s.%i", prefix, i);

+

+        if (qobject_type(value) == QTYPE_QDICT) {

+            qdict_flatten_qdict(qobject_to(QDict, value), target, new_key);

+        } else if (qobject_type(value) == QTYPE_QLIST) {

+            qdict_flatten_qlist(qobject_to(QList, value), target, new_key);

+        } else {

+            /* All other types are moved to the target unchanged. */

+            qdict_put_obj(target, new_key, qobject_ref(value));

+        }

+

+        g_free(new_key);

+    }

+}

+

+static void qdict_flatten_qdict(QDict *qdict, QDict *target, const char *prefix)

+{

+    QObject *value;

+    const QDictEntry *entry, *next;

+    char *new_key;

+    bool delete;

+

+    entry = qdict_first(qdict);

+

+    while (entry != NULL) {

+

+        next = qdict_next(qdict, entry);

+        value = qdict_entry_value(entry);

+        new_key = NULL;

+        delete = false;

+

+        if (prefix) {

+            new_key = g_strdup_printf("%s.%s", prefix, entry->key);

+        }

+

+        if (qobject_type(value) == QTYPE_QDICT) {

+            /* Entries of QDicts are processed recursively, the QDict object

+             * itself disappears. */

+            qdict_flatten_qdict(qobject_to(QDict, value), target,

+                                new_key ? new_key : entry->key);

+            delete = true;

+        } else if (qobject_type(value) == QTYPE_QLIST) {

+            qdict_flatten_qlist(qobject_to(QList, value), target,

+                                new_key ? new_key : entry->key);

+            delete = true;

+        } else if (prefix) {

+            /* All other objects are moved to the target unchanged. */

+            qdict_put_obj(target, new_key, qobject_ref(value));

+            delete = true;

+        }

+

+        g_free(new_key);

+

+        if (delete) {

+            qdict_del(qdict, entry->key);

+

+            /* Restart loop after modifying the iterated QDict */

+            entry = qdict_first(qdict);

+            continue;

+        }

+

+        entry = next;

+    }

+}

+

+/**

+ * qdict_flatten(): For each nested QDict with key x, all fields with key y

+ * are moved to this QDict and their key is renamed to "x.y". For each nested

+ * QList with key x, the field at index y is moved to this QDict with the key

+ * "x.y" (i.e., the reverse of what qdict_array_split() does).

+ * This operation is applied recursively for nested QDicts and QLists.

+ */

+void qdict_flatten(QDict *qdict)

+{

+    qdict_flatten_qdict(qdict, qdict, NULL);

+}

+

+/* extract all the src QDict entries starting by start into dst */

+void qdict_extract_subqdict(QDict *src, QDict **dst, const char *start)

+

+{

+    const QDictEntry *entry, *next;

+    const char *p;

+

+    *dst = qdict_new();

+    entry = qdict_first(src);

+

+    while (entry != NULL) {

+        next = qdict_next(src, entry);

+        if (strstart(entry->key, start, &p)) {

+            qdict_put_obj(*dst, p, qobject_ref(entry->value));

+            qdict_del(src, entry->key);

+        }

+        entry = next;

+    }

+}

+

+static int qdict_count_prefixed_entries(const QDict *src, const char *start)

+{

+    const QDictEntry *entry;

+    int count = 0;

+

+    for (entry = qdict_first(src); entry; entry = qdict_next(src, entry)) {

+        if (strstart(entry->key, start, NULL)) {

+            if (count == INT_MAX) {

+                return -ERANGE;

+            }

+            count++;

+        }

+    }

+

+    return count;

+}

+

+/**

+ * qdict_array_split(): This function moves array-like elements of a QDict into

+ * a new QList. Every entry in the original QDict with a key "%u" or one

+ * prefixed "%u.", where %u designates an unsigned integer starting at 0 and

+ * incrementally counting up, will be moved to a new QDict at index %u in the

+ * output QList with the key prefix removed, if that prefix is "%u.". If the

+ * whole key is just "%u", the whole QObject will be moved unchanged without

+ * creating a new QDict. The function terminates when there is no entry in the

+ * QDict with a prefix directly (incrementally) following the last one; it also

+ * returns if there are both entries with "%u" and "%u." for the same index %u.

+ * Example: {"0.a": 42, "0.b": 23, "1.x": 0, "4.y": 1, "o.o": 7, "2": 66}

+ *      (or {"1.x": 0, "4.y": 1, "0.a": 42, "o.o": 7, "0.b": 23, "2": 66})

+ *       => [{"a": 42, "b": 23}, {"x": 0}, 66]

+ *      and {"4.y": 1, "o.o": 7} (remainder of the old QDict)

+ */

+void qdict_array_split(QDict *src, QList **dst)

+{

+    unsigned i;

+

+    *dst = qlist_new();

+

+    for (i = 0; i < UINT_MAX; i++) {

+        QObject *subqobj;

+        bool is_subqdict;

+        QDict *subqdict;

+        char indexstr[32], prefix[32];

+        size_t snprintf_ret;

+

+        snprintf_ret = snprintf(indexstr, 32, "%u", i);

+        assert(snprintf_ret < 32);

+

+        subqobj = qdict_get(src, indexstr);

+

+        snprintf_ret = snprintf(prefix, 32, "%u.", i);

+        assert(snprintf_ret < 32);

+

+        /* Overflow is the same as positive non-zero results */

+        is_subqdict = qdict_count_prefixed_entries(src, prefix);

+

+        /*

+         * There may be either a single subordinate object (named

+         * "%u") or multiple objects (each with a key prefixed "%u."),

+         * but not both.

+         */

+        if (!subqobj == !is_subqdict) {

+            break;

+        }

+

+        if (is_subqdict) {

+            qdict_extract_subqdict(src, &subqdict, prefix);

+            assert(qdict_size(subqdict) > 0);

+        } else {

+            qobject_ref(subqobj);

+            qdict_del(src, indexstr);

+        }

+

+        qlist_append_obj(*dst, subqobj ?: QOBJECT(subqdict));

+    }

+}

+

+/**

+ * qdict_split_flat_key:

+ * @key: the key string to split

+ * @prefix: non-NULL pointer to hold extracted prefix

+ * @suffix: non-NULL pointer to remaining suffix

+ *

+ * Given a flattened key such as 'foo.0.bar', split it into two parts

+ * at the first '.' separator. Allows double dot ('..') to escape the

+ * normal separator.

+ *

+ * e.g.

+ *    'foo.0.bar' -> prefix='foo' and suffix='0.bar'

+ *    'foo..0.bar' -> prefix='foo.0' and suffix='bar'

+ *

+ * The '..' sequence will be unescaped in the returned 'prefix'

+ * string. The 'suffix' string will be left in escaped format, so it

+ * can be fed back into the qdict_split_flat_key() key as the input

+ * later.

+ *

+ * The caller is responsible for freeing the string returned in @prefix

+ * using g_free().

+ */

+static void qdict_split_flat_key(const char *key, char **prefix,

+                                 const char **suffix)

+{

+    const char *separator;

+    size_t i, j;

+

+    /* Find first '.' separator, but if there is a pair '..'

+     * that acts as an escape, so skip over '..' */

+    separator = NULL;

+    do {

+        if (separator) {

+            separator += 2;

+        } else {

+            separator = key;

+        }

+        separator = strchr(separator, '.');

+    } while (separator && separator[1] == '.');

+

+    if (separator) {

+        *prefix = g_strndup(key, separator - key);

+        *suffix = separator + 1;

+    } else {

+        *prefix = g_strdup(key);

+        *suffix = NULL;

+    }

+

+    /* Unescape the '..' sequence into '.' */

+    for (i = 0, j = 0; (*prefix)[i] != '\0'; i++, j++) {

+        if ((*prefix)[i] == '.') {

+            assert((*prefix)[i + 1] == '.');

+            i++;

+        }

+        (*prefix)[j] = (*prefix)[i];

+    }

+    (*prefix)[j] = '\0';

+}

+

+/**

+ * qdict_is_list:

+ * @maybe_list: dict to check if keys represent list elements.

+ *

+ * Determine whether all keys in @maybe_list are valid list elements.

+ * If @maybe_list is non-zero in length and all the keys look like

+ * valid list indexes, this will return 1. If @maybe_list is zero

+ * length or all keys are non-numeric then it will return 0 to indicate

+ * it is a normal qdict. If there is a mix of numeric and non-numeric

+ * keys, or the list indexes are non-contiguous, an error is reported.

+ *

+ * Returns: 1 if a valid list, 0 if a dict, -1 on error

+ */

+static int qdict_is_list(QDict *maybe_list, Error **errp)

+{

+    const QDictEntry *ent;

+    ssize_t len = 0;

+    ssize_t max = -1;

+    int is_list = -1;

+    int64_t val;

+

+    for (ent = qdict_first(maybe_list); ent != NULL;

+         ent = qdict_next(maybe_list, ent)) {

+

+        if (qemu_strtoi64(ent->key, NULL, 10, &val) == 0) {

+            if (is_list == -1) {

+                is_list = 1;

+            } else if (!is_list) {

+                error_setg(errp,

+                           "Cannot mix list and non-list keys");

+                return -1;

+            }

+            len++;

+            if (val > max) {

+                max = val;

+            }

+        } else {

+            if (is_list == -1) {

+                is_list = 0;

+            } else if (is_list) {

+                error_setg(errp,

+                           "Cannot mix list and non-list keys");

+                return -1;

+            }

+        }

+    }

+

+    if (is_list == -1) {

+        assert(!qdict_size(maybe_list));

+        is_list = 0;

+    }

+

+    /* NB this isn't a perfect check - e.g. it won't catch

+     * a list containing '1', '+1', '01', '3', but that

+     * does not matter - we've still proved that the

+     * input is a list. It is up the caller to do a

+     * stricter check if desired */

+    if (len != (max + 1)) {

+        error_setg(errp, "List indices are not contiguous, "

+                   "saw %zd elements but %zd largest index",

+                   len, max);

+        return -1;

+    }

+

+    return is_list;

+}

+

+/**

+ * qdict_crumple:

+ * @src: the original flat dictionary (only scalar values) to crumple

+ *

+ * Takes a flat dictionary whose keys use '.' separator to indicate

+ * nesting, and values are scalars, and crumples it into a nested

+ * structure.

+ *

+ * To include a literal '.' in a key name, it must be escaped as '..'

+ *

+ * For example, an input of:

+ *

+ * { 'foo.0.bar': 'one', 'foo.0.wizz': '1',

+ *   'foo.1.bar': 'two', 'foo.1.wizz': '2' }

+ *

+ * will result in an output of:

+ *

+ * {

+ *   'foo': [

+ *      { 'bar': 'one', 'wizz': '1' },

+ *      { 'bar': 'two', 'wizz': '2' }

+ *   ],

+ * }

+ *

+ * The following scenarios in the input dict will result in an

+ * error being returned:

+ *

+ *  - Any values in @src are non-scalar types

+ *  - If keys in @src imply that a particular level is both a

+ *    list and a dict. e.g., "foo.0.bar" and "foo.eek.bar".

+ *  - If keys in @src imply that a particular level is a list,

+ *    but the indices are non-contiguous. e.g. "foo.0.bar" and

+ *    "foo.2.bar" without any "foo.1.bar" present.

+ *  - If keys in @src represent list indexes, but are not in

+ *    the "%zu" format. e.g. "foo.+0.bar"

+ *

+ * Returns: either a QDict or QList for the nested data structure, or NULL

+ * on error

+ */

+QObject *qdict_crumple(const QDict *src, Error **errp)

+{

+    const QDictEntry *ent;

+    QDict *two_level, *multi_level = NULL;

+    QObject *dst = NULL, *child;

+    size_t i;

+    char *prefix = NULL;

+    const char *suffix = NULL;

+    int is_list;

+

+    two_level = qdict_new();

+

+    /* Step 1: split our totally flat dict into a two level dict */

+    for (ent = qdict_first(src); ent != NULL; ent = qdict_next(src, ent)) {

+        if (qobject_type(ent->value) == QTYPE_QDICT ||

+            qobject_type(ent->value) == QTYPE_QLIST) {

+            error_setg(errp, "Value %s is not a scalar",

+                       ent->key);

+            goto error;

+        }

+

+        qdict_split_flat_key(ent->key, &prefix, &suffix);

+

+        child = qdict_get(two_level, prefix);

+        if (suffix) {

+            QDict *child_dict = qobject_to(QDict, child);

+            if (!child_dict) {

+                if (child) {

+                    error_setg(errp, "Key %s prefix is already set as a scalar",

+                               prefix);

+                    goto error;

+                }

+

+                child_dict = qdict_new();

+                qdict_put_obj(two_level, prefix, QOBJECT(child_dict));

+            }

+

+            qdict_put_obj(child_dict, suffix, qobject_ref(ent->value));

+        } else {

+            if (child) {

+                error_setg(errp, "Key %s prefix is already set as a dict",

+                           prefix);

+                goto error;

+            }

+            qdict_put_obj(two_level, prefix, qobject_ref(ent->value));

+        }

+

+        g_free(prefix);

+        prefix = NULL;

+    }

+

+    /* Step 2: optionally process the two level dict recursively

+     * into a multi-level dict */

+    multi_level = qdict_new();

+    for (ent = qdict_first(two_level); ent != NULL;

+         ent = qdict_next(two_level, ent)) {

+        QDict *dict = qobject_to(QDict, ent->value);

+        if (dict) {

+            child = qdict_crumple(dict, errp);

+            if (!child) {

+                goto error;

+            }

+

+            qdict_put_obj(multi_level, ent->key, child);

+        } else {

+            qdict_put_obj(multi_level, ent->key, qobject_ref(ent->value));

+        }

+    }

+    qobject_unref(two_level);

+    two_level = NULL;

+

+    /* Step 3: detect if we need to turn our dict into list */

+    is_list = qdict_is_list(multi_level, errp);

+    if (is_list < 0) {

+        goto error;

+    }

+

+    if (is_list) {

+        dst = QOBJECT(qlist_new());

+

+        for (i = 0; i < qdict_size(multi_level); i++) {

+            char *key = g_strdup_printf("%zu", i);

+

+            child = qdict_get(multi_level, key);

+            g_free(key);

+

+            if (!child) {

+                error_setg(errp, "Missing list index %zu", i);

+                goto error;

+            }

+

+            qlist_append_obj(qobject_to(QList, dst), qobject_ref(child));

+        }

+        qobject_unref(multi_level);

+        multi_level = NULL;

+    } else {

+        dst = QOBJECT(multi_level);

+    }

+

+    return dst;

+

+ error:

+    g_free(prefix);

+    qobject_unref(multi_level);

+    qobject_unref(two_level);

+    qobject_unref(dst);

+    return NULL;

+}

+

+/**

+ * qdict_array_entries(): Returns the number of direct array entries if the

+ * sub-QDict of src specified by the prefix in subqdict (or src itself for

+ * prefix == "") is valid as an array, i.e. the length of the created list if

+ * the sub-QDict would become empty after calling qdict_array_split() on it. If

+ * the array is not valid, -EINVAL is returned.

+ */

+int qdict_array_entries(QDict *src, const char *subqdict)

+{

+    const QDictEntry *entry;

+    unsigned i;

+    unsigned entries = 0;

+    size_t subqdict_len = strlen(subqdict);

+

+    assert(!subqdict_len || subqdict[subqdict_len - 1] == '.');

+

+    /* qdict_array_split() loops until UINT_MAX, but as we want to return

+     * negative errors, we only have a signed return value here. Any additional

+     * entries will lead to -EINVAL. */

+    for (i = 0; i < INT_MAX; i++) {

+        QObject *subqobj;

+        int subqdict_entries;

+        char *prefix = g_strdup_printf("%s%u.", subqdict, i);

+

+        subqdict_entries = qdict_count_prefixed_entries(src, prefix);

+

+        /* Remove ending "." */

+        prefix[strlen(prefix) - 1] = 0;

+        subqobj = qdict_get(src, prefix);

+

+        g_free(prefix);

+

+        if (subqdict_entries < 0) {

+            return subqdict_entries;

+        }

+

+        /* There may be either a single subordinate object (named "%u") or

+         * multiple objects (each with a key prefixed "%u."), but not both. */

+        if (subqobj && subqdict_entries) {

+            return -EINVAL;

+        } else if (!subqobj && !subqdict_entries) {

+            break;

+        }

+

+        entries += subqdict_entries ? subqdict_entries : 1;

+    }

+

+    /* Consider everything handled that isn't part of the given sub-QDict */

+    for (entry = qdict_first(src); entry; entry = qdict_next(src, entry)) {

+        if (!strstart(qdict_entry_key(entry), subqdict, NULL)) {

+            entries++;

+        }

+    }

+

+    /* Anything left in the sub-QDict that wasn't handled? */

+    if (qdict_size(src) != entries) {

+        return -EINVAL;

+    }

+

+    return i;

+}

+

+/**

+ * qdict_join(): Absorb the src QDict into the dest QDict, that is, move all

+ * elements from src to dest.

+ *

+ * If an element from src has a key already present in dest, it will not be

+ * moved unless overwrite is true.

+ *

+ * If overwrite is true, the conflicting values in dest will be discarded and

+ * replaced by the corresponding values from src.

+ *

+ * Therefore, with overwrite being true, the src QDict will always be empty when

+ * this function returns. If overwrite is false, the src QDict will be empty

+ * iff there were no conflicts.

+ */

+void qdict_join(QDict *dest, QDict *src, bool overwrite)

+{

+    const QDictEntry *entry, *next;

+

+    entry = qdict_first(src);

+    while (entry) {

+        next = qdict_next(src, entry);

+

+        if (overwrite || !qdict_haskey(dest, entry->key)) {

+            qdict_put_obj(dest, entry->key, qobject_ref(entry->value));

+            qdict_del(src, entry->key);

+        }

+

+        entry = next;

+    }

+}

+

+/**

+ * qdict_rename_keys(): Rename keys in qdict according to the replacements

+ * specified in the array renames. The array must be terminated by an entry

+ * with from = NULL.

+ *

+ * The renames are performed individually in the order of the array, so entries

+ * may be renamed multiple times and may or may not conflict depending on the

+ * order of the renames array.

+ *

+ * Returns true for success, false in error cases.

+ */

+bool qdict_rename_keys(QDict *qdict, const QDictRenames *renames, Error **errp)

+{

+    QObject *qobj;

+

+    while (renames->from) {

+        if (qdict_haskey(qdict, renames->from)) {

+            if (qdict_haskey(qdict, renames->to)) {

+                error_setg(errp, "'%s' and its alias '%s' can't be used at the "

+                           "same time", renames->to, renames->from);

+                return false;

+            }

+

+            qobj = qdict_get(qdict, renames->from);

+            qdict_put_obj(qdict, renames->to, qobject_ref(qobj));

+            qdict_del(qdict, renames->from);

+        }

+

+        renames++;

+    }

+    return true;

+}

diff --git a/qobject/qdict.c b/qobject/qdict.c

index 0554c64..3d8c2f7 100644

--- a/qobject/qdict.c

+++ b/qobject/qdict.c

@@ -11,17 +11,11 @@

  */

 #include "qemu/osdep.h"

-#include "block/qdict.h"

 #include "qapi/qmp/qnum.h"

 #include "qapi/qmp/qdict.h"

 #include "qapi/qmp/qbool.h"

-#include "qapi/qmp/qlist.h"

 #include "qapi/qmp/qnull.h"

 #include "qapi/qmp/qstring.h"

-#include "qapi/error.h"

-#include "qemu/queue.h"

-#include "qemu-common.h"