X-Git-Url: http://git.annexia.org/?p=virt-top.git;a=blobdiff_plain;f=libvirt%2Flibvirt.mli;h=72917ef4eab34c77e021a67f6d4d5132ba4c0593;hp=aa4b9f44dbe226429b5cac20fdf42cad9b4fe2ae;hb=cf1b8052e9bca746a90dc4380bf4d6b09399adf2;hpb=38e7a75efaab8a6a709cbad8342bca4a45ead8cc diff --git a/libvirt/libvirt.mli b/libvirt/libvirt.mli index aa4b9f4..72917ef 100644 --- a/libvirt/libvirt.mli +++ b/libvirt/libvirt.mli @@ -1,6 +1,6 @@ -(** OCaml bindings for libvirt. - (C) Copyright 2007 Richard W.M. Jones, Red Hat Inc. - http://libvirt.org/ +(** OCaml bindings for libvirt. *) +(* (C) Copyright 2007 Richard W.M. Jones, Red Hat Inc. + http://libvirt.org/ This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public @@ -17,16 +17,185 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA *) +(** + {2 Introduction and examples} + + This is a set of bindings for writing OCaml programs to + manage virtual machines through {{:http://libvirt.org/}libvirt}. + + {3 Using libvirt interactively} + + Using the interactive toplevel: + +{v +$ ocaml -I +libvirt + Objective Caml version 3.10.0 + +# #load "unix.cma";; +# #load "mllibvirt.cma";; +# let name = "test:///default";; +val name : string = "test:///default" +# let conn = Libvirt.Connect.connect_readonly ~name () ;; +val conn : Libvirt.ro Libvirt.Connect.t = +# Libvirt.Connect.get_node_info conn;; + : Libvirt.Connect.node_info = +{Libvirt.Connect.model = "i686"; Libvirt.Connect.memory = 3145728L; + Libvirt.Connect.cpus = 16; Libvirt.Connect.mhz = 1400; + Libvirt.Connect.nodes = 2; Libvirt.Connect.sockets = 2; + Libvirt.Connect.cores = 2; Libvirt.Connect.threads = 2} +v} + + {3 Compiling libvirt programs} + + This command compiles a program to native code: + +{v +ocamlopt -I +libvirt mllibvirt.cmxa list_domains.ml -o list_domains +v} + + {3 Example: Connect to the hypervisor} + + The main modules are {!Libvirt.Connect}, {!Libvirt.Domain} and + {!Libvirt.Network} corresponding respectively to the + {{:http://libvirt.org/html/libvirt-libvirt.html}virConnect*, virDomain* and virNetwork* functions from libvirt}. + For brevity I usually rename these modules like this: + +{v +module C = Libvirt.Connect +module D = Libvirt.Domain +module N = Libvirt.Network +v} + + To get a connection handle, assuming a Xen hypervisor: + +{v +let name = "xen:///" +let conn = C.connect_readonly ~name () +v} + + {3 Example: List running domains} + +{v +open Printf + +let n = C.num_of_domains conn in +let ids = C.list_domains conn n in +let domains = Array.map (D.lookup_by_id conn) ids in +Array.iter ( + fun dom -> + printf "%8d %s\n%!" (D.get_id dom) (D.get_name dom) +) domains; +v} + + {3 Example: List inactive domains} + +{v +let n = C.num_of_defined_domains conn in +let names = C.list_defined_domains conn n in +Array.iter ( + fun name -> + printf "inactive %s\n%!" name +) names; +v} + + {3 Example: Print node info} + +{v +let node_info = C.get_node_info conn in +printf "model = %s\n" node_info.C.model; +printf "memory = %Ld K\n" node_info.C.memory; +printf "cpus = %d\n" node_info.C.cpus; +printf "mhz = %d\n" node_info.C.mhz; +printf "nodes = %d\n" node_info.C.nodes; +printf "sockets = %d\n" node_info.C.sockets; +printf "cores = %d\n" node_info.C.cores; +printf "threads = %d\n%!" node_info.C.threads; + +let hostname = C.get_hostname conn in +printf "hostname = %s\n%!" hostname; + +let uri = C.get_uri conn in +printf "uri = %s\n%!" uri +v} + +*) + + +(** {2 Programming issues} + + {3 General safety issues} + + Memory allocation / automatic garbage collection of all libvirt + objects should be completely safe (except in the specific + virterror case noted below). If you find any safety issues or if your + pure OCaml program ever segfaults, please contact the author. + + You can force a libvirt object to be freed early by calling + the [close] function on the object. This shouldn't affect + the safety of garbage collection and should only be used when + you want to explicitly free memory. Note that explicitly + closing a connection object does nothing if there are still + unclosed domain or network objects referencing it. + + Note that even though you hold open (eg) a domain object, that + doesn't mean that the domain (virtual machine) actually exists. + The domain could have been shut down or deleted by another user. + Thus domain objects can through odd exceptions at any time. + This is just the nature of virtualisation. + + Virterror has a specific design error which means that the + objects embedded in a virterror exception message are only + valid as long as the connection handle is still open. This + is a design flaw in the C code of libvirt and we cannot fix + or work around it in the OCaml bindings. + + {3 Backwards and forwards compatibility} + + OCaml-libvirt is backwards and forwards compatible with + any libvirt >= 0.2.1. One consequence of this is that + your program can dynamically link to a {i newer} version of + libvirt than it was compiled with, and it should still + work. + + When we link to an older version of libvirt.so, there may + be missing functions. If ocaml-libvirt was compiled with + gcc, then these are turned into OCaml {!Libvirt.Not_supported} + exceptions. + + We don't support libvirt < 0.2.1, and never will so don't ask us. + + {3 Threads} + + You can issue multiple concurrent libvirt requests in + different threads. However you must follow this rule: + Each thread must have its own separate libvirt connection, {i or} + you must implement your own mutex scheme to ensure that no + two threads can ever make concurrent calls using the same + libvirt connection. + + (Note that multithreaded code is not well tested. If you find + bugs please report them.) + + {3 Initialisation} + + Libvirt requires all callers to call virInitialize before + using the library. This is done automatically for you by + these bindings when the program starts up, and we believe + that the way this is done is safe. + + {2 Reference} +*) + type uuid = string -(** This is a "raw" UUID, ie. a packed string of bytes. *) + (** This is a "raw" UUID, ie. a packed string of bytes. *) type xml = string -(** Type of XML (an uninterpreted string of bytes). Use PXP, expat, - xml-light, etc. if you want to do anything useful with the XML. -*) + (** Type of XML (an uninterpreted string of bytes). Use PXP, expat, + xml-light, etc. if you want to do anything useful with the XML. + *) type filename = string -(** A filename. *) + (** A filename. *) val get_version : ?driver:string -> unit -> int * int (** [get_version ()] returns the library version in the first part @@ -46,12 +215,37 @@ val uuid_length : int val uuid_string_length : int (** Length of UUID strings. *) -(* These phantom types are used to ensure the type-safety of read-only - * versus read-write connections. For more information see: - * http://caml.inria.fr/pub/ml-archives/caml-list/2004/07/80683af867cce6bf8fff273973f70c95.en.html - *) type rw = [`R|`W] type ro = [`R] + (** These + {{:http://caml.inria.fr/pub/ml-archives/caml-list/2004/07/80683af867cce6bf8fff273973f70c95.en.html}phantom types} + are used to ensure the type-safety of read-only + versus read-write connections. + + All connection/domain/etc. objects are marked with + a phantom read-write or read-only type, and trying to + pass a read-only object into a function which could + mutate the object will cause a compile time error. + + Each module provides a function like {!Libvirt.Connect.const} + to demote a read-write object into a read-only object. The + opposite operation is, of course, not allowed. + + If you want to handle both read-write and read-only + connections at runtime, use a variant similar to this: +{v +type conn_t = + | No_connection + | Read_only of Libvirt.ro Libvirt.Connect.t + | Read_write of Libvirt.rw Libvirt.Connect.t +v} + See also the source of [mlvirsh]. + *) + +type ('a, 'b) job_t +(** Forward definition of {!Job.t} to avoid recursive module dependencies. *) + +(** {3 Connections} *) module Connect : sig @@ -136,6 +330,15 @@ sig Call {!num_of_defined_networks} first to get a value for [max]. *) + val num_of_pools : [>`R] t -> int + (** Returns the number of storage pools. *) + val list_pools : [>`R] t -> int -> string array + (** Return list of storage pools. *) + val num_of_defined_pools : [>`R] t -> int + (** Returns the number of storage pools. *) + val list_defined_pools : [>`R] t -> int -> string array + (** Return list of storage pools. *) + (* The name of this function is inconsistent, but the inconsistency * is really in libvirt itself. *) @@ -182,8 +385,9 @@ sig *) end (** Module dealing with connections. [Connect.t] is the - connection object. - *) + connection object. *) + +(** {3 Domains} *) module Domain : sig @@ -244,6 +448,8 @@ sig (** Create a new guest domain (not necessarily a Linux one) from the given XML. *) + val create_linux_job : [>`W] Connect.t -> xml -> ([`Domain], rw) job_t + (** Asynchronous domain creation. *) val lookup_by_id : 'a Connect.t -> int -> 'a t (** Lookup a domain by ID. *) val lookup_by_uuid : 'a Connect.t -> uuid -> 'a t @@ -268,10 +474,16 @@ sig (** Resume a domain. *) val save : [>`W] t -> filename -> unit (** Suspend a domain, then save it to the file. *) + val save_job : [>`W] t -> filename -> ([`Domain_nocreate], rw) job_t + (** Asynchronous domain suspend. *) val restore : [>`W] Connect.t -> filename -> unit (** Restore a domain from a file. *) + val restore_job : [>`W] Connect.t -> filename -> ([`Domain_nocreate], rw) job_t + (** Asynchronous domain restore. *) val core_dump : [>`W] t -> filename -> unit (** Force a domain to core dump to the named file. *) + val core_dump_job : [>`W] t -> filename -> ([`Domain_nocreate], rw) job_t + (** Asynchronous core dump. *) val shutdown : [>`W] t -> unit (** Shutdown a domain. *) val reboot : [>`W] t -> unit @@ -313,6 +525,8 @@ sig (** Undefine a domain - removes its configuration. *) val create : [>`W] t -> unit (** Launch a defined (inactive) domain. *) + val create_job : [>`W] t -> ([`Domain_nocreate], rw) job_t + (** Asynchronous launch domain. *) val get_autostart : [>`R] t -> bool (** Get the autostart flag for a domain. *) val set_autostart : [>`W] t -> bool -> unit @@ -358,8 +572,9 @@ sig *) end (** Module dealing with domains. [Domain.t] is the - domain object. - *) + domain object. *) + +(** {3 Networks} *) module Network : sig @@ -376,12 +591,16 @@ sig (** Lookup a network by UUID string. *) val create_xml : [>`W] Connect.t -> xml -> rw t (** Create a network. *) + val create_xml_job : [>`W] Connect.t -> xml -> ([`Network], rw) job_t + (** Asynchronous create network. *) val define_xml : [>`W] Connect.t -> xml -> rw t (** Define but don't activate a network. *) val undefine : [>`W] t -> unit (** Undefine configuration of a network. *) val create : [>`W] t -> unit (** Start up a defined (inactive) network. *) + val create_job : [>`W] t -> ([`Network_nocreate], rw) job_t + (** Asynchronous start network. *) val destroy : [>`W] t -> unit (** Destroy a network. *) val free : [>`R] t -> unit @@ -413,8 +632,192 @@ sig *) end (** Module dealing with networks. [Network.t] is the - network object. - *) + network object. *) + +(** {3 Storage pools} *) + +module Pool : +sig + type 'rw t + (** Storage pool handle. *) + + type pool_state = Inactive | Active + (** State of the storage pool. *) + + type pool_info = { + state : pool_state; (** Inactive | Active *) + capacity : int64; (** Logical size in bytes. *) + allocation : int64; (** Currently allocated in bytes. *) + } + + val lookup_by_name : 'a Connect.t -> string -> 'a t + val lookup_by_uuid : 'a Connect.t -> uuid -> 'a t + val lookup_by_uuid_string : 'a Connect.t -> string -> 'a t + (** Look up a storage pool by name, UUID or UUID string. *) + + val create_xml : [>`W] Connect.t -> xml -> rw t + (** Create a storage pool. *) + val define_xml : [>`W] Connect.t -> xml -> rw t + (** Define but don't activate a storage pool. *) + val undefine : [>`W] t -> unit + (** Undefine configuration of a storage pool. *) + val create : [>`W] t -> unit + (** Start up a defined (inactive) storage pool. *) + val destroy : [>`W] t -> unit + (** Destroy a storage pool. *) + val shutdown : [>`W] t -> unit + (** Shutdown a storage pool. *) + val free : [>`R] t -> unit + (** Free a storage pool object in memory. + + The storage pool object is automatically freed if it is garbage + collected. This function just forces it to be freed right + away. + *) + val refresh : [`R] t -> unit + (** Refresh the list of volumes in the storage pool. *) + + val get_name : [`R] t -> string + (** Name of the pool. *) + val get_uuid : [`R] t -> uuid + (** Get the UUID (as a packed byte array). *) + val get_uuid_string : [`R] t -> string + (** Get the UUID (as a printable string). *) + val get_info : [`R] t -> pool_info + (** Get information about the pool. *) + val get_xml_desc : [`R] t -> xml + (** Get the XML description. *) + val get_autostart : [`R] t -> bool + (** Get the autostart flag for the storage pool. *) + val set_autostart : [`W] t -> bool -> unit + (** Set the autostart flag for the storage pool. *) + + external const : [>`R] t -> ro t = "%identity" + (** [const conn] turns a read/write storage pool into a read-only + pool. Note that the opposite operation is impossible. + *) +end + (** Module dealing with storage pools. *) + +(** {3 Storage volumes} *) + +module Volume : +sig + type 'rw t + (** Storage volume handle. *) + + type vol_type = File | Block | Virtual + (** Type of a storage volume. *) + + type vol_info = { + typ : vol_type; (** Type of storage volume. *) + capacity : int64; (** Logical size in bytes. *) + allocation : int64; (** Currently allocated in bytes. *) + } + + val lookup_by_name : 'a Pool.t -> string -> 'a t + val lookup_by_key : 'a Pool.t -> string -> 'a t + val lookup_by_path : 'a Pool.t -> string -> 'a t + (** Look up a storage volume by name, key or path volume. *) + + val pool_of_volume : 'a t -> 'a Pool.t + (** Get the storage pool containing this volume. *) + + val get_name : [`R] t -> string + (** Name of the volume. *) + val get_key : [`R] t -> string + (** Key of the volume. *) + val get_path : [`R] t -> string + (** Path of the volume. *) + val get_info : [`R] t -> vol_info + (** Get information about the storage volume. *) + val get_xml_desc : [`R] t -> xml + (** Get the XML description. *) + + val create_xml : [`W] Pool.t -> xml -> unit + (** Create a storage volume. *) + val destroy : [`W] t -> unit + (** Destroy a storage volume. *) + val free : [>`R] t -> unit + (** Free a storage volume object in memory. + + The storage volume object is automatically freed if it is garbage + collected. This function just forces it to be freed right + away. + *) + + external const : [>`R] t -> ro t = "%identity" + (** [const conn] turns a read/write storage volume into a read-only + volume. Note that the opposite operation is impossible. + *) +end + (** Module dealing with storage volumes. *) + +(** {3 Jobs and asynchronous processing} *) + +module Job : +sig + type ('jobclass, 'rw) t = ('jobclass, 'rw) job_t + (** A background asynchronous job. + + Jobs represent a pending operation such as domain creation. + The possible types for a job are: + +{v +(`Domain, `W) Job.t Job creating a new domain +(`Domain_nocreate, `W) Job.t Job acting on an existing domain +(`Network, `W) Job.t Job creating a new network +(`Network_nocreate, `W) Job.t Job acting on an existing network +v} + *) + + type job_type = Bounded | Unbounded + (** A Bounded job is one where we can estimate time to completion. *) + + type job_state = Running | Complete | Failed | Cancelled + (** State of the job. *) + + type job_info = { + typ : job_type; (** Job type (Bounded, Unbounded) *) + state : job_state; (** Job state (Running, etc.) *) + running_time : int; (** Actual running time (seconds) *) + (** The following fields are only available in Bounded jobs: *) + remaining_time : int; (** Estimated time left (seconds) *) + percent_complete : int (** Estimated percent complete *) + } + + val get_info : ('a,'b) t -> job_info + (** Get information and status about the job. *) + + val get_domain : ([`Domain], 'a) t -> 'a Domain.t + (** Get the completed domain from a job. + + You should only call it on a job in state Complete. *) + + val get_network : ([`Network], 'a) t -> 'a Network.t + (** Get the completed network from a job. + + You should only call it on a job in state Complete. *) + + val cancel : ('a,'b) t -> unit + (** Cancel a job. *) + + val free : ('a, [>`R]) t -> unit + (** Free a job object in memory. + + The job object is automatically freed if it is garbage + collected. This function just forces it to be freed right + away. + *) + + external const : ('a, [>`R]) t -> ('a, ro) t = "%identity" + (** [const conn] turns a read/write job into a read-only + job. Note that the opposite operation is impossible. + *) +end + (** Module dealing with asynchronous jobs. *) + +(** {3 Error handling and exceptions} *) module Virterror : sig @@ -464,7 +867,14 @@ sig | VIR_ERR_NO_DOMAIN | VIR_ERR_NO_NETWORK | VIR_ERR_INVALID_MAC - (* ^^ NB: If you add a variant you MUST edit libvirt_c.c:MAX_VIR_* *) + | VIR_ERR_AUTH_FAILED + | VIR_ERR_INVALID_STORAGE_POOL + | VIR_ERR_INVALID_STORAGE_VOL + | VIR_WAR_NO_STORAGE + | VIR_ERR_NO_STORAGE_POOL + | VIR_ERR_NO_STORAGE_VOL + (* ^^ NB: If you add a variant you MUST edit + libvirt_c_epilogue.c:MAX_VIR_* *) | VIR_ERR_UNKNOWN of int (** See [] for meaning of these codes. *) @@ -488,7 +898,9 @@ sig | VIR_FROM_OPENVZ | VIR_FROM_XENXM | VIR_FROM_STATS_LINUX - (* ^^ NB: If you add a variant you MUST edit libvirt_c.c: MAX_VIR_* *) + | VIR_FROM_STORAGE + (* ^^ NB: If you add a variant you MUST edit + libvirt_c_epilogue.c: MAX_VIR_* *) | VIR_FROM_UNKNOWN of int (** Subsystem / driver which produced the error. *) @@ -550,12 +962,16 @@ exception Virterror of Virterror.t (** This exception can be raised by any library function that detects an error. To get a printable error message, call {!Virterror.to_string} on the content of this exception. +*) - Note that functions may also raise - [Invalid_argument "virFoo not supported"] - (where virFoo is the libvirt function name) if a function is - not supported at either compile or runtime. This applies to +exception Not_supported of string +(** + Functions may raise + [Not_supported "virFoo"] + (where [virFoo] is the libvirt function name) if a function is + not supported at either compile or run time. This applies to any libvirt function added after version 0.2.1. - See also [http://libvirt.org/hvsupport.html] + + See also {{:http://libvirt.org/hvsupport.html}http://libvirt.org/hvsupport.html} *)