__PMFREEATTRSSPEC(3) - Linux man page online | Library functions
Host and.
Chapter
PCP
PMPARSEHOSTATTRSSPEC(3) Library Functions Manual PMPARSEHOSTATTRSSPEC(3)
@firewalls.r.us?compress
pcps://nas1.servers.com?user=otto&pass=blotto&compress
If the specified protocol is a unix domain socket protocol, the path to the socket in the
local file system may be specified along with optional attributes which are to be associ‐
ated with the connection. For example:
unix://$PCP_RUN_DIR/pmcd.socket:?compress
local://my/local/pmcd.socket:?user=otto&pass=blotto&compress
If the optional protocol component is not specified, then the default setting will be used
- which is the native PCP binary protocol. However, this can still be overwritten via the
environment as described in PCPIntro(1). If the protocol prefix is specified, it must be
one of either "pcp://" (clear), "pcps://" (secure, encrypted), "unix://" (authenticated
local) or "local://" ("unix://" then "pcp://").
The path specified for the "unix://" and "local://" protocols will always be interpreted
as an absolute path name. For example, the following are all interpreted identically as
$PCP_RUN_DIR/pmcd.socket.
unix://$PCP_RUN_DIR/pmcd.socket
unix:/$PCP_RUN_DIR/pmcd.socket
unix:$PCP_RUN_DIR/pmcd.socket
Refer to __pmParseHostSpec(3) for further details of the host and proxy host components.
If any optional connection attributes are to be specified, these are separated from the
hostname component via the '?' character. Each attribute is separated by the '&' charac‐
ter, and each can be either a simple attribute flag (such as "compress") or a name=value
pair (such as "username=fred").
__pmParseHostAttrsSpec takes a null-terminated host-and-attributes specification string
and returns an array of pmHostSpec structures, where the array has count entries, and an
attrs hash table containing any attributes (including the optional protocol, if it was
specified).
Full details of the pmHostSpec structures are provided in __pmParseHostSpec(3).
The __pmHashCtl structure that is filled out on return via attributes, represents each in‐
dividual attribute in the specification string with any associated value. It should be
considered an opaque structure and should be zeroed beforehand.
The returned hash table control structure can be iterated using one of the supplied itera‐
tion mechanisms - __pmHashWalkCB (a callback-based mechanism) or __pmHashWalk (a simple
procedural mechanism). These provide access to the individual hash nodes, as __pmHashNode
entries, which provide access to decoded attributes and their (optional) values.
typedef struct __pmHashNode {
__pmHashNode *next; /* next node in hash bucket (internal) */
unsigned int key; /* key identifying particular attribute */
void *data; /* attributes value (optional, string) */
} __pmHashNode;
There are a set number of valid attributes, however these may be extended in future re‐
leases as new connection parameters become needed. These can be identified via the
PCP_ATTR_* macros in the PCP header files.
__pmUnparseHostSpec performs the inverse operation, creating a string representation from
hosts and attributes structures. The size of the supplied string buffer must be provided
by the caller using the size parameter.
NAME
__pmParseHostAttrsSpec, __pmUnparseHostAttrsSpec, __pmFreeHostAttrsSpec, __pmFreeAttrsSpec - host and attributes specification parserC SYNOPSIS
#include "pmapi.h" #include "libpcp.h" int __pmParseHostAttrsSpec(const char *string, pmHostSpec **hostsp, int *count, __pmHashCtl *attrs, char **errmsg); int __pmUnparseHostAttrsSpec(pmHostSpec *hostsp, int *count, __pmHashCtl *attrs, char *string, size_t size); void __pmFreeHostAttrsSpec(pmHostSpec *hosts, int count, __pmHashCtl *attrs); void __pmFreeAttrsSpec(__pmHashCtl *attrs); cc ... -lpcpCAVEAT
This documentation is intended for internal Performance Co-Pilot (PCP) developer use. These interfaces are not part of the PCP APIs that are guaranteed to remain fixed across releases, and they may not work, or may provide different semantics at some point in the future.DESCRIPTION
__pmParseHostAttrsSpec accepts a string specifying the location of a PCP performance met‐ ric collector daemon, and any attributes that should be associated with the connection to that daemon. The syntax allows the optional specification of a protocol (native PCP protocol, encrypted PCP protocol or unix domain socket protocol). If the specified protocol is native PCP protocol, or encrypted PCP protocol, an initial pmcd(1) hostname with optional port numbers and optional proxy host, and optional at‐ tributes which are to be associated with the connection may be specified. Some examples follow: pcp://nas1.servers.com:@firewalls.r.us?compress
pcps://nas1.servers.com?user=otto&pass=blotto&compress
If the specified protocol is a unix domain socket protocol, the path to the socket in the
local file system may be specified along with optional attributes which are to be associ‐
ated with the connection. For example:
unix://$PCP_RUN_DIR/pmcd.socket:?compress
local://my/local/pmcd.socket:?user=otto&pass=blotto&compress
If the optional protocol component is not specified, then the default setting will be used
- which is the native PCP binary protocol. However, this can still be overwritten via the
environment as described in PCPIntro(1). If the protocol prefix is specified, it must be
one of either "pcp://" (clear), "pcps://" (secure, encrypted), "unix://" (authenticated
local) or "local://" ("unix://" then "pcp://").
The path specified for the "unix://" and "local://" protocols will always be interpreted
as an absolute path name. For example, the following are all interpreted identically as
$PCP_RUN_DIR/pmcd.socket.
unix://$PCP_RUN_DIR/pmcd.socket
unix:/$PCP_RUN_DIR/pmcd.socket
unix:$PCP_RUN_DIR/pmcd.socket
Refer to __pmParseHostSpec(3) for further details of the host and proxy host components.
If any optional connection attributes are to be specified, these are separated from the
hostname component via the '?' character. Each attribute is separated by the '&' charac‐
ter, and each can be either a simple attribute flag (such as "compress") or a name=value
pair (such as "username=fred").
__pmParseHostAttrsSpec takes a null-terminated host-and-attributes specification string
and returns an array of pmHostSpec structures, where the array has count entries, and an
attrs hash table containing any attributes (including the optional protocol, if it was
specified).
Full details of the pmHostSpec structures are provided in __pmParseHostSpec(3).
The __pmHashCtl structure that is filled out on return via attributes, represents each in‐
dividual attribute in the specification string with any associated value. It should be
considered an opaque structure and should be zeroed beforehand.
The returned hash table control structure can be iterated using one of the supplied itera‐
tion mechanisms - __pmHashWalkCB (a callback-based mechanism) or __pmHashWalk (a simple
procedural mechanism). These provide access to the individual hash nodes, as __pmHashNode
entries, which provide access to decoded attributes and their (optional) values.
typedef struct __pmHashNode {
__pmHashNode *next; /* next node in hash bucket (internal) */
unsigned int key; /* key identifying particular attribute */
void *data; /* attributes value (optional, string) */
} __pmHashNode;
There are a set number of valid attributes, however these may be extended in future re‐
leases as new connection parameters become needed. These can be identified via the
PCP_ATTR_* macros in the PCP header files.
__pmUnparseHostSpec performs the inverse operation, creating a string representation from
hosts and attributes structures. The size of the supplied string buffer must be provided
by the caller using the size parameter.
RETURN VALUE
If the given string is successfully parsed __pmParseHostAttrsSpec returns zero. In this case the dynamic storage allocated by __pmParseHostAttrsSpec can be released by calling __pmFreeHostAttrsSpec using the addresses returned from __pmParseHostAttrsSpec Alternatively, the hosts and attributes memory can be freed separately, using __pmFree‐ HostSpec(3) and __pmFreeAttrsSpec. __pmParseHostAttrsSpec returns PM_ERR_GENERIC and a dynamically allocated error message string in errmsg, if the given string does not parse, and the user-supplied errmsg pointer is non-null. Be sure to free(3) the error message string in this situation. In the case of an error, both hosts and attributes are undefined. In the case of success, errmsg is undefined. On success __pmUnparseHostAttrsSpec returns a positive value indicating the number of characters written into the supplied buffer. However, if the supplied buffer was too small, a negative status code of -E2BIG will be returned.SEE ALSO
pmcd(1), pmproxy(1), pmchart(1), __pmParseHostSpec(3), PMAPI(3) and pmNewContext(3).| This manual | Reference | Other manuals |
|---|---|---|
| __pmFreeAttrsSpec(3) | referred by | __pmFreeHostSpec(3) |
| refer to | malloc(3) | PCPIntro(1) | PMAPI(3) | pmcd(1) | pmchart(1) | __pmFreeHostSpec(3) | pmNewContext(3) | pmproxy(1) |