qemu-e2k/util/keyval.c

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keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
/*
* Parsing KEY=VALUE,... strings
*
* Copyright (C) 2017 Red Hat Inc.
*
* Authors:
* Markus Armbruster <armbru@redhat.com>,
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
/*
* KEY=VALUE,... syntax:
*
* key-vals = [ key-val { ',' key-val } [ ',' ] ]
* key-val = key '=' val
* key = key-fragment { '.' key-fragment }
* key-fragment = / [^=,.]* /
* val = { / [^,]* / | ',,' }
*
* Semantics defined by reduction to JSON:
*
* key-vals specifies a JSON object, i.e. a tree whose root is an
* object, inner nodes other than the root are objects or arrays,
* and leaves are strings.
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
*
* Each key-val = key-fragment '.' ... '=' val specifies a path from
* root to a leaf (left of '='), and the leaf's value (right of
* '=').
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
*
* A path from the root is defined recursively:
* L '.' key-fragment is a child of the node denoted by path L
* key-fragment is a child of the tree root
* If key-fragment is numeric, the parent is an array and the child
* is its key-fragment-th member, counting from zero.
* Else, the parent is an object, and the child is its member named
* key-fragment.
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
*
* This constrains inner nodes to be either array or object. The
* constraints must be satisfiable. Counter-example: a.b=1,a=2 is
* not, because root.a must be an object to satisfy a.b=1 and a
* string to satisfy a=2.
*
* Array subscripts can occur in any order, but the set of
* subscripts must not have gaps. For instance, a.1=v is not okay,
* because root.a[0] is missing.
*
* If multiple key-val denote the same leaf, the last one determines
* the value.
*
* Key-fragments must be valid QAPI names or consist only of decimal
* digits.
*
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
* The length of any key-fragment must be between 1 and 127.
*
* Design flaw: there is no way to denote an empty array or non-root
* object. While interpreting "key absent" as empty seems natural
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
* (removing a key-val from the input string removes the member when
* there are more, so why not when it's the last), it doesn't work:
* "key absent" already means "optional object/array absent", which
* isn't the same as "empty object/array present".
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
*
* Design flaw: scalar values can only be strings; there is no way to
* denote numbers, true, false or null. The special QObject input
* visitor returned by qobject_input_visitor_new_keyval() mostly hides
* this by automatically converting strings to the type the visitor
qapi: Reject alternates that can't work with keyval_parse() Alternates are sum types like unions, but use the JSON type on the wire / QType in QObject instead of an explicit tag. That's why we require alternate members to have distinct QTypes. The recently introduced keyval_parse() (commit d454dbe) can only produce string scalars. The qobject_input_visitor_new_keyval() input visitor mostly hides the difference, so code using a QObject input visitor doesn't have to care whether its input was parsed from JSON or KEY=VALUE,... The difference leaks for alternates, as noted in commit 0ee9ae7: a non-string, non-enum scalar alternate value can't currently be expressed. In part, this is just our insufficiently sophisticated implementation. Consider alternate type 'GuestFileWhence'. It has an integer member and a 'QGASeek' member. The latter is an enumeration with values 'set', 'cur', 'end'. The meaning of b=set, b=cur, b=end, b=0, b=1 and so forth is perfectly obvious. However, our current implementation falls apart at run time for b=0, b=1, and so forth. Fixable, but not today; add a test case and a TODO comment. Now consider an alternate type with a string and an integer member. What's the meaning of a=42? Is it the string "42" or the integer 42? Whichever meaning you pick makes the other inexpressible. This isn't just an implementation problem, it's fundamental. Our current implementation will pick string. So far, we haven't needed such alternates. To make sure we stop and think before we add one that cannot sanely work with keyval_parse(), let's require alternate members to have sufficiently distinct representation in KEY=VALUE,... syntax: * A string member clashes with any other scalar member * An enumeration member clashes with bool members when it has value 'on' or 'off'. * An enumeration member clashes with numeric members when it has a value that starts with '-', '+', or a decimal digit. This is a rather lazy approximation of the actual number syntax accepted by the visitor. Note that enumeration values starting with '-' and '+' are rejected elsewhere already, but better safe than sorry. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1495471335-23707-5-git-send-email-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-05-22 18:42:15 +02:00
* expects. Breaks down for type 'any', where the visitor's
* expectation isn't clear. Code visiting 'any' needs to do the
* conversion itself, but only when using this keyval visitor.
* Awkward. Note that we carefully restrict alternate types to avoid
* similar ambiguity.
*
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
* Additional syntax for use with an implied key:
*
* key-vals-ik = val-no-key [ ',' key-vals ]
* val-no-key = / [^=,]* /
*
* where no-key is syntactic sugar for implied-key=val-no-key.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qapi/qmp/qstring.h"
#include "qemu/cutils.h"
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
#include "qemu/option.h"
/*
* Convert @key to a list index.
* Convert all leading decimal digits to a (non-negative) number,
* capped at INT_MAX.
* If @end is non-null, assign a pointer to the first character after
* the number to *@end.
* Else, fail if any characters follow.
* On success, return the converted number.
* On failure, return a negative value.
* Note: since only digits are converted, no two keys can map to the
* same number, except by overflow to INT_MAX.
*/
static int key_to_index(const char *key, const char **end)
{
int ret;
unsigned long index;
if (*key < '0' || *key > '9') {
return -EINVAL;
}
ret = qemu_strtoul(key, end, 10, &index);
if (ret) {
return ret == -ERANGE ? INT_MAX : ret;
}
return index <= INT_MAX ? index : INT_MAX;
}
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
/*
* Ensure @cur maps @key_in_cur the right way.
* If @value is null, it needs to map to a QDict, else to this
* QString.
* If @cur doesn't have @key_in_cur, put an empty QDict or @value,
* respectively.
* Else, if it needs to map to a QDict, and already does, do nothing.
* Else, if it needs to map to this QString, and already maps to a
* QString, replace it by @value.
* Else, fail because we have conflicting needs on how to map
* @key_in_cur.
* In any case, take over the reference to @value, i.e. if the caller
* wants to hold on to a reference, it needs to QINCREF().
* Use @key up to @key_cursor to identify the key in error messages.
* On success, return the mapped value.
* On failure, store an error through @errp and return NULL.
*/
static QObject *keyval_parse_put(QDict *cur,
const char *key_in_cur, QString *value,
const char *key, const char *key_cursor,
Error **errp)
{
QObject *old, *new;
old = qdict_get(cur, key_in_cur);
if (old) {
if (qobject_type(old) != (value ? QTYPE_QSTRING : QTYPE_QDICT)) {
error_setg(errp, "Parameters '%.*s.*' used inconsistently",
(int)(key_cursor - key), key);
QDECREF(value);
return NULL;
}
if (!value) {
return old; /* already QDict, do nothing */
}
new = QOBJECT(value); /* replacement */
} else {
new = value ? QOBJECT(value) : QOBJECT(qdict_new());
}
qdict_put_obj(cur, key_in_cur, new);
return new;
}
/*
* Parse one KEY=VALUE from @params, store result in @qdict.
* The first fragment of KEY applies to @qdict. Subsequent fragments
* apply to nested QDicts, which are created on demand. @implied_key
* is as in keyval_parse().
* On success, return a pointer to the next KEY=VALUE, or else to '\0'.
* On failure, return NULL.
*/
static const char *keyval_parse_one(QDict *qdict, const char *params,
const char *implied_key,
Error **errp)
{
const char *key, *key_end, *s, *end;
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
size_t len;
char key_in_cur[128];
QDict *cur;
int ret;
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
QObject *next;
QString *val;
key = params;
len = strcspn(params, "=,");
if (implied_key && len && key[len] != '=') {
/* Desugar implied key */
key = implied_key;
len = strlen(implied_key);
}
key_end = key + len;
/*
* Loop over key fragments: @s points to current fragment, it
* applies to @cur. @key_in_cur[] holds the previous fragment.
*/
cur = qdict;
s = key;
for (;;) {
/* Want a key index (unless it's first) or a QAPI name */
if (s != key && key_to_index(s, &end) >= 0) {
len = end - s;
} else {
ret = parse_qapi_name(s, false);
len = ret < 0 ? 0 : ret;
}
assert(s + len <= key_end);
if (!len || (s + len < key_end && s[len] != '.')) {
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
assert(key != implied_key);
error_setg(errp, "Invalid parameter '%.*s'",
(int)(key_end - key), key);
return NULL;
}
if (len >= sizeof(key_in_cur)) {
assert(key != implied_key);
error_setg(errp, "Parameter%s '%.*s' is too long",
s != key || s + len != key_end ? " fragment" : "",
(int)len, s);
return NULL;
}
if (s != key) {
next = keyval_parse_put(cur, key_in_cur, NULL,
key, s - 1, errp);
if (!next) {
return NULL;
}
cur = qobject_to_qdict(next);
assert(cur);
}
memcpy(key_in_cur, s, len);
key_in_cur[len] = 0;
s += len;
if (*s != '.') {
break;
}
s++;
}
if (key == implied_key) {
assert(!*s);
s = params;
} else {
if (*s != '=') {
error_setg(errp, "Expected '=' after parameter '%.*s'",
(int)(s - key), key);
return NULL;
}
s++;
}
val = qstring_new();
for (;;) {
if (!*s) {
break;
} else if (*s == ',') {
s++;
if (*s != ',') {
break;
}
}
qstring_append_chr(val, *s++);
}
if (!keyval_parse_put(cur, key_in_cur, val, key, key_end, errp)) {
return NULL;
}
return s;
}
static char *reassemble_key(GSList *key)
{
GString *s = g_string_new("");
GSList *p;
for (p = key; p; p = p->next) {
g_string_prepend_c(s, '.');
g_string_prepend(s, (char *)p->data);
}
return g_string_free(s, FALSE);
}
/*
* Listify @cur recursively.
* Replace QDicts whose keys are all valid list indexes by QLists.
* @key_of_cur is the list of key fragments leading up to @cur.
* On success, return either @cur or its replacement.
* On failure, store an error through @errp and return NULL.
*/
static QObject *keyval_listify(QDict *cur, GSList *key_of_cur, Error **errp)
{
GSList key_node;
bool has_index, has_member;
const QDictEntry *ent;
QDict *qdict;
QObject *val;
char *key;
size_t nelt;
QObject **elt;
int index, max_index, i;
QList *list;
key_node.next = key_of_cur;
/*
* Recursively listify @cur's members, and figure out whether @cur
* itself is to be listified.
*/
has_index = false;
has_member = false;
for (ent = qdict_first(cur); ent; ent = qdict_next(cur, ent)) {
if (key_to_index(ent->key, NULL) >= 0) {
has_index = true;
} else {
has_member = true;
}
qdict = qobject_to_qdict(ent->value);
if (!qdict) {
continue;
}
key_node.data = ent->key;
val = keyval_listify(qdict, &key_node, errp);
if (!val) {
return NULL;
}
if (val != ent->value) {
qdict_put_obj(cur, ent->key, val);
}
}
if (has_index && has_member) {
key = reassemble_key(key_of_cur);
error_setg(errp, "Parameters '%s*' used inconsistently", key);
g_free(key);
return NULL;
}
if (!has_index) {
return QOBJECT(cur);
}
/* Copy @cur's values to @elt[] */
nelt = qdict_size(cur) + 1; /* one extra, for use as sentinel */
elt = g_new0(QObject *, nelt);
max_index = -1;
for (ent = qdict_first(cur); ent; ent = qdict_next(cur, ent)) {
index = key_to_index(ent->key, NULL);
assert(index >= 0);
if (index > max_index) {
max_index = index;
}
/*
* We iterate @nelt times. If we get one exceeding @nelt
* here, we will put less than @nelt values into @elt[],
* triggering the error in the next loop.
*/
if ((size_t)index >= nelt - 1) {
continue;
}
/* Even though dict keys are distinct, indexes need not be */
elt[index] = ent->value;
}
/*
* Make a list from @elt[], reporting the first missing element,
* if any.
* If we dropped an index >= nelt in the previous loop, this loop
* will run into the sentinel and report index @nelt missing.
*/
list = qlist_new();
assert(!elt[nelt-1]); /* need the sentinel to be null */
for (i = 0; i < MIN(nelt, max_index + 1); i++) {
if (!elt[i]) {
key = reassemble_key(key_of_cur);
error_setg(errp, "Parameter '%s%d' missing", key, i);
g_free(key);
g_free(elt);
QDECREF(list);
return NULL;
}
qobject_incref(elt[i]);
qlist_append_obj(list, elt[i]);
}
g_free(elt);
return QOBJECT(list);
}
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
/*
* Parse @params in QEMU's traditional KEY=VALUE,... syntax.
* If @implied_key, the first KEY= can be omitted. @implied_key is
* implied then, and VALUE can't be empty or contain ',' or '='.
* On success, return a dictionary of the parsed keys and values.
* On failure, store an error through @errp and return NULL.
*/
QDict *keyval_parse(const char *params, const char *implied_key,
Error **errp)
{
QDict *qdict = qdict_new();
QObject *listified;
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
const char *s;
s = params;
while (*s) {
s = keyval_parse_one(qdict, s, implied_key, errp);
if (!s) {
QDECREF(qdict);
return NULL;
}
implied_key = NULL;
}
listified = keyval_listify(qdict, NULL, errp);
if (!listified) {
QDECREF(qdict);
return NULL;
}
assert(listified == QOBJECT(qdict));
keyval: New keyval_parse() keyval_parse() parses KEY=VALUE,... into a QDict. Works like qemu_opts_parse(), except: * Returns a QDict instead of a QemuOpts (d'oh). * Supports nesting, unlike QemuOpts: a KEY is split into key fragments at '.' (dotted key convention; the block layer does something similar on top of QemuOpts). The key fragments are QDict keys, and the last one's value is updated to VALUE. * Each key fragment may be up to 127 bytes long. qemu_opts_parse() limits the entire key to 127 bytes. * Overlong key fragments are rejected. qemu_opts_parse() silently truncates them. * Empty key fragments are rejected. qemu_opts_parse() happily accepts empty keys. * It does not store the returned value. qemu_opts_parse() stores it in the QemuOptsList. * It does not treat parameter "id" specially. qemu_opts_parse() ignores all but the first "id", and fails when its value isn't id_wellformed(), or duplicate (a QemuOpts with the same ID is already stored). It also screws up when a value contains ",id=". * Implied value is not supported. qemu_opts_parse() desugars "foo" to "foo=on", and "nofoo" to "foo=off". * An implied key's value can't be empty, and can't contain ','. I intend to grow this into a saner replacement for QemuOpts. It'll take time, though. Note: keyval_parse() provides no way to do lists, and its key syntax is incompatible with the __RFQDN_ prefix convention for downstream extensions, because it blindly splits at '.', even in __RFQDN_. Both issues will be addressed later in the series. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
2017-02-28 22:26:49 +01:00
return qdict;
}