diff mbox series

[libmnl,v3,2/2] libmnl: add support for signed types

Message ID 20220808175020.2983706-2-jacob.e.keller@intel.com
State Changes Requested
Delegated to: Pablo Neira
Headers show
Series [libmnl,v3,1/2] libmnl: update attribute function comments to use \return | expand

Commit Message

Keller, Jacob E Aug. 8, 2022, 5:50 p.m. UTC
libmnl has get and put functions for unsigned integer types. It lacks
support for the signed variations. On some level this is technically
sufficient. A user could use the unsigned variations and then cast to a
signed value at use. However, this makes resulting code in the application
more difficult to follow. Introduce signed variations of the integer get
and put functions.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
Changes since v2
* Fixed the ABI breakage (oops!)

 include/libmnl/libmnl.h |  16 ++++
 src/attr.c              | 194 +++++++++++++++++++++++++++++++++++++++-
 2 files changed, 209 insertions(+), 1 deletion(-)

Comments

Pablo Neira Ayuso Aug. 16, 2022, 9:46 p.m. UTC | #1
On Mon, Aug 08, 2022 at 10:50:20AM -0700, Jacob Keller wrote:
> libmnl has get and put functions for unsigned integer types. It lacks
> support for the signed variations. On some level this is technically
> sufficient. A user could use the unsigned variations and then cast to a
> signed value at use. However, this makes resulting code in the application
> more difficult to follow. Introduce signed variations of the integer get
> and put functions.
> 
> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> ---
> Changes since v2
> * Fixed the ABI breakage (oops!)
> 
>  include/libmnl/libmnl.h |  16 ++++
>  src/attr.c              | 194 +++++++++++++++++++++++++++++++++++++++-

I'm missing one more update for src/libmnl.map.

BTW, how does the library size increase after these new symbols?
diff mbox series

Patch

diff --git a/include/libmnl/libmnl.h b/include/libmnl/libmnl.h
index 4bd0b92e8742..ccee4948ff2f 100644
--- a/include/libmnl/libmnl.h
+++ b/include/libmnl/libmnl.h
@@ -92,6 +92,10 @@  extern uint8_t mnl_attr_get_u8(const struct nlattr *attr);
 extern uint16_t mnl_attr_get_u16(const struct nlattr *attr);
 extern uint32_t mnl_attr_get_u32(const struct nlattr *attr);
 extern uint64_t mnl_attr_get_u64(const struct nlattr *attr);
+extern int8_t mnl_attr_get_s8(const struct nlattr *attr);
+extern int16_t mnl_attr_get_s16(const struct nlattr *attr);
+extern int32_t mnl_attr_get_s32(const struct nlattr *attr);
+extern int64_t mnl_attr_get_s64(const struct nlattr *attr);
 extern const char *mnl_attr_get_str(const struct nlattr *attr);
 
 /* TLV attribute putters */
@@ -100,6 +104,10 @@  extern void mnl_attr_put_u8(struct nlmsghdr *nlh, uint16_t type, uint8_t data);
 extern void mnl_attr_put_u16(struct nlmsghdr *nlh, uint16_t type, uint16_t data);
 extern void mnl_attr_put_u32(struct nlmsghdr *nlh, uint16_t type, uint32_t data);
 extern void mnl_attr_put_u64(struct nlmsghdr *nlh, uint16_t type, uint64_t data);
+extern void mnl_attr_put_s8(struct nlmsghdr *nlh, uint16_t type, int8_t data);
+extern void mnl_attr_put_s16(struct nlmsghdr *nlh, uint16_t type, int16_t data);
+extern void mnl_attr_put_s32(struct nlmsghdr *nlh, uint16_t type, int32_t data);
+extern void mnl_attr_put_s64(struct nlmsghdr *nlh, uint16_t type, int64_t data);
 extern void mnl_attr_put_str(struct nlmsghdr *nlh, uint16_t type, const char *data);
 extern void mnl_attr_put_strz(struct nlmsghdr *nlh, uint16_t type, const char *data);
 
@@ -109,6 +117,10 @@  extern bool mnl_attr_put_u8_check(struct nlmsghdr *nlh, size_t buflen, uint16_t
 extern bool mnl_attr_put_u16_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint16_t data);
 extern bool mnl_attr_put_u32_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint32_t data);
 extern bool mnl_attr_put_u64_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint64_t data);
+extern bool mnl_attr_put_s8_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, int8_t data);
+extern bool mnl_attr_put_s16_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, int16_t data);
+extern bool mnl_attr_put_s32_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, int32_t data);
+extern bool mnl_attr_put_s64_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, int64_t data);
 extern bool mnl_attr_put_str_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, const char *data);
 extern bool mnl_attr_put_strz_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, const char *data);
 
@@ -134,6 +146,10 @@  enum mnl_attr_data_type {
 	MNL_TYPE_NESTED_COMPAT,
 	MNL_TYPE_NUL_STRING,
 	MNL_TYPE_BINARY,
+	MNL_TYPE_S8,
+	MNL_TYPE_S16,
+	MNL_TYPE_S32,
+	MNL_TYPE_S64,
 	MNL_TYPE_MAX,
 };
 
diff --git a/src/attr.c b/src/attr.c
index 20d48a370524..2f31ecbe8f7a 100644
--- a/src/attr.c
+++ b/src/attr.c
@@ -203,6 +203,10 @@  static const size_t mnl_attr_data_type_len[MNL_TYPE_MAX] = {
 	[MNL_TYPE_U16]		= sizeof(uint16_t),
 	[MNL_TYPE_U32]		= sizeof(uint32_t),
 	[MNL_TYPE_U64]		= sizeof(uint64_t),
+	[MNL_TYPE_S8]		= sizeof(int8_t),
+	[MNL_TYPE_S16]		= sizeof(int16_t),
+	[MNL_TYPE_S32]		= sizeof(int32_t),
+	[MNL_TYPE_S64]		= sizeof(int64_t),
 	[MNL_TYPE_MSECS]	= sizeof(uint64_t),
 };
 
@@ -390,7 +394,55 @@  EXPORT_SYMBOL uint64_t mnl_attr_get_u64(const struct nlattr *attr)
 }
 
 /**
- * mnl_attr_get_str - get pointer to string attribute
+ * mnl_attr_get_s8 - get 8-bit signed integer attribute payload
+ * \param attr pointer to netlink attribute
+ *
+ * \return 8-bit value of the attribute payload
+ */
+EXPORT_SYMBOL int8_t mnl_attr_get_s8(const struct nlattr *attr)
+{
+	return *((int8_t *)mnl_attr_get_payload(attr));
+}
+
+/**
+ * mnl_attr_get_s16 - get 16-bit signed integer attribute payload
+ * \param attr pointer to netlink attribute
+ *
+ * \return 16-bit value of the attribute payload
+ */
+EXPORT_SYMBOL int16_t mnl_attr_get_s16(const struct nlattr *attr)
+{
+	return *((int16_t *)mnl_attr_get_payload(attr));
+}
+
+/**
+ * mnl_attr_get_s32 - get 32-bit signed integer attribute payload
+ * \param attr pointer to netlink attribute
+ *
+ * \return 32-bit value of the attribute payload
+ */
+EXPORT_SYMBOL int32_t mnl_attr_get_s32(const struct nlattr *attr)
+{
+	return *((int32_t *)mnl_attr_get_payload(attr));
+}
+
+/**
+ * mnl_attr_get_s64 - get 64-bit signed integer attribute payload
+ * \param attr pointer to netlink attribute
+ *
+ * This function reads the 64-bit nlattr payload in an alignment safe manner.
+ *
+ * \return 64-bit value of the attribute payload
+ */
+EXPORT_SYMBOL int64_t mnl_attr_get_s64(const struct nlattr *attr)
+{
+	int64_t tmp;
+	memcpy(&tmp, mnl_attr_get_payload(attr), sizeof(tmp));
+	return tmp;
+}
+
+/**
+  * mnl_attr_get_str - get pointer to string attribute
  * \param attr pointer to netlink attribute
  *
  * \return string pointer of the attribute payload
@@ -487,6 +539,66 @@  EXPORT_SYMBOL void mnl_attr_put_u64(struct nlmsghdr *nlh, uint16_t type,
 	mnl_attr_put(nlh, type, sizeof(uint64_t), &data);
 }
 
+/**
+ * mnl_attr_put_s8 - add 8-bit signed integer attribute to netlink message
+ * \param nlh pointer to the netlink message
+ * \param type netlink attribute type
+ * \param data 8-bit signed integer data that is stored by the new attribute
+ *
+ * This function updates the length field of the Netlink message (nlmsg_len)
+ * by adding the size (header + payload) of the new attribute.
+ */
+EXPORT_SYMBOL void mnl_attr_put_s8(struct nlmsghdr *nlh, uint16_t type,
+				   int8_t data)
+{
+	mnl_attr_put(nlh, type, sizeof(int8_t), &data);
+}
+
+/**
+ * mnl_attr_put_s16 - add 16-bit signed integer attribute to netlink message
+ * \param nlh pointer to the netlink message
+ * \param type netlink attribute type
+ * \param data 16-bit signed integer data that is stored by the new attribute
+ *
+ * This function updates the length field of the Netlink message (nlmsg_len)
+ * by adding the size (header + payload) of the new attribute.
+ */
+EXPORT_SYMBOL void mnl_attr_put_s16(struct nlmsghdr *nlh, uint16_t type,
+				    int16_t data)
+{
+	mnl_attr_put(nlh, type, sizeof(int16_t), &data);
+}
+
+/**
+ * mnl_attr_put_s32 - add 32-bit signed integer attribute to netlink message
+ * \param nlh pointer to the netlink message
+ * \param type netlink attribute type
+ * \param data 32-bit signed integer data that is stored by the new attribute
+ *
+ * This function updates the length field of the Netlink message (nlmsg_len)
+ * by adding the size (header + payload) of the new attribute.
+ */
+EXPORT_SYMBOL void mnl_attr_put_s32(struct nlmsghdr *nlh, uint16_t type,
+				    int32_t data)
+{
+	mnl_attr_put(nlh, type, sizeof(int32_t), &data);
+}
+
+/**
+ * mnl_attr_put_s64 - add 64-bit signed integer attribute to netlink message
+ * \param nlh pointer to the netlink message
+ * \param type netlink attribute type
+ * \param data 64-bit signed integer data that is stored by the new attribute
+ *
+ * This function updates the length field of the Netlink message (nlmsg_len)
+ * by adding the size (header + payload) of the new attribute.
+ */
+EXPORT_SYMBOL void mnl_attr_put_s64(struct nlmsghdr *nlh, uint16_t type,
+				    int64_t data)
+{
+	mnl_attr_put(nlh, type, sizeof(int64_t), &data);
+}
+
 /**
  * mnl_attr_put_str - add string attribute to netlink message
  * \param nlh  pointer to the netlink message
@@ -647,6 +759,86 @@  EXPORT_SYMBOL bool mnl_attr_put_u64_check(struct nlmsghdr *nlh, size_t buflen,
 	return mnl_attr_put_check(nlh, buflen, type, sizeof(uint64_t), &data);
 }
 
+/**
+ * mnl_attr_put_s8_check - add 8-bit signed int attribute to netlink message
+ * \param nlh pointer to the netlink message
+ * \param buflen size of buffer which stores the message
+ * \param type netlink attribute type
+ * \param data 8-bit signed integer data that is stored by the new attribute
+ *
+ * This function first checks that the data can be added to the message
+ * (fits into the buffer) and then updates the length field of the Netlink
+ * message (nlmsg_len) by adding the size (header + payload) of the new
+ * attribute.
+ *
+ * \return true if the attribute could be added, false otherwise
+ */
+EXPORT_SYMBOL bool mnl_attr_put_s8_check(struct nlmsghdr *nlh, size_t buflen,
+					 uint16_t type, int8_t data)
+{
+	return mnl_attr_put_check(nlh, buflen, type, sizeof(data), &data);
+}
+
+/**
+ * mnl_attr_put_s16_check - add 16-bit signed int attribute to netlink message
+ * \param nlh pointer to the netlink message
+ * \param buflen size of buffer which stores the message
+ * \param type netlink attribute type
+ * \param data 16-bit signed integer data that is stored by the new attribute
+ *
+ * This function first checks that the data can be added to the message
+ * (fits into the buffer) and then updates the length field of the Netlink
+ * message (nlmsg_len) by adding the size (header + payload) of the new
+ * attribute.
+ *
+ * \return true if the attribute could be added, false otherwise
+ */
+EXPORT_SYMBOL bool mnl_attr_put_s16_check(struct nlmsghdr *nlh, size_t buflen,
+					  uint16_t type, int16_t data)
+{
+	return mnl_attr_put_check(nlh, buflen, type, sizeof(data), &data);
+}
+
+/**
+ * mnl_attr_put_s32_check - add 32-bit signed int attribute to netlink message
+ * \param nlh pointer to the netlink message
+ * \param buflen size of buffer which stores the message
+ * \param type netlink attribute type
+ * \param data 32-bit signed integer data that is stored by the new attribute
+ *
+ * This function first checks that the data can be added to the message
+ * (fits into the buffer) and then updates the length field of the Netlink
+ * message (nlmsg_len) by adding the size (header + payload) of the new
+ * attribute.
+ *
+ * \return true if the attribute could be added, false otherwise
+ */
+EXPORT_SYMBOL bool mnl_attr_put_s32_check(struct nlmsghdr *nlh, size_t buflen,
+					  uint16_t type, int32_t data)
+{
+	return mnl_attr_put_check(nlh, buflen, type, sizeof(data), &data);
+}
+
+/**
+ * mnl_attr_put_s64_check - add 64-bit signed int attribute to netlink message
+ * \param nlh pointer to the netlink message
+ * \param buflen size of buffer which stores the message
+ * \param type netlink attribute type
+ * \param data 64-bit signed integer data that is stored by the new attribute
+ *
+ * This function first checks that the data can be added to the message
+ * (fits into the buffer) and then updates the length field of the Netlink
+ * message (nlmsg_len) by adding the size (header + payload) of the new
+ * attribute.
+ *
+ * \return true if the attribute could be added, false otherwise
+ */
+EXPORT_SYMBOL bool mnl_attr_put_s64_check(struct nlmsghdr *nlh, size_t buflen,
+					  uint16_t type, int64_t data)
+{
+	return mnl_attr_put_check(nlh, buflen, type, sizeof(data), &data);
+}
+
 /**
  * mnl_attr_put_str_check - add string attribute to netlink message
  * \param nlh  pointer to the netlink message