The following commit message is shared with 4 patches.
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Under the newlib interface most of our 'get' functions
represent a bit of a compromise in that the actual raw
values are coerced into one (probably ok) return type.
That approach creates the possibility of truncation at
best, and wouldn't serve future needs should something
other than numeric data be added to the 'get' results.
This commit trades the current compromise for a return
value guaranteed to satisfy all future needs, namely a
pointer to a particular api's specific results struct.
The impact on existing programs is minimal, especially
when using a new supplied macro. Otherwise, native 'C'
syntax could be used, but may feel somewhat unnatural.
[ as an aside, this new approach allows us to delete ]
[ all 'getsfunc' table entries & the supporting code ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Following is a summary of significant changes (if any)
to each of these now upgraded 3rd gen library modules.
<meminfo> ............................................
. eliminated duplicate decl of 'struct procps_meminfo'
. standardized/normalized results struct union members
. added 'std' & 'var' dividers in .c file, like <pids>
. how did i miss relocating all these friggin' #undefs
. cleanup 'get' return logic (remove a redundant 'if')
<pids> ...............................................
. repositioned the procps_pidsinfo structure in header
. removed the extra trailing comma from enum pids_item
. standardized/normalized results struct union members
<slabinfo> ...........................................
. corrected comment typo (jeeze, in an 'aligned' para)
. standardized/normalized results struct union members
. added 'std' & 'var' dividers in .c file, like <pids>
. removed an obsolete #undef from procps_slabinfo_sort
. cleanup 'get' return logic (remove a redundant 'if')
<stat> ...............................................
. how did i miss relocating all these friggin' #undefs
. corrected an initialization fencepost used with numa <=== see Craig, here's a bug fix
. removed the extra trailing comma from enum stat_item
. standardized/normalized results struct union members
. added 'std' & 'var' dividers in .c file, like <pids>
. strengthen those parm checks in procps_stat_get func
. cleanup 'get' return logic (remove a redundant 'if')
<vmstat> .............................................
. standardized/normalized results struct union members
. added 'std' & 'var' dividers in .c file, like <pids>
. cleanup 'get' return logic (remove a redundant 'if')
[ virtually all of these tweaks reflect the author's ]
[ continuing pursuit of an unreasonable goal -- that ]
[ of a 'perfect' (plus 'pretty') C language program! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
With the dust now settling on all those 3rd generation
upgrades, this patch tries to provide some consistency
among the separate modules involved. Someday we should
consider a 4th generation where all redundant code has
been removed and isolated in a new shared source file.
Following is a summary of significant changes (if any)
to each of these now upgraded 3rd gen library modules.
<meminfo> ............................................
. strictly formatting/comment changes, code unaffected
<pids> ...............................................
. replaced a local mkSTR macro with existing STRINGIFY
. added fetch narrative explaining duplicate addresses
<slabinfo> ...........................................
. rearranged some free logic for procps_slabinfo_unref
. added fetch narrative explaining duplicate addresses
<stat> ...............................................
. added #define ENFORCE_LOGICAL, just as in <slabinfo>
. replaced a local mkSTR macro with existing STRINGIFY
. alphabetized the function declarations in the header
<vmstat> .............................................
. made one coverity concession with read_vmstat_failed
[ several of these changes may reflect this author's ]
[ continuing pursuit of an unreasonable goal -- that ]
[ of a 'perfect' (plus 'pretty') C language program! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Oops, the PROCPS_VMSTAT_logical_end enum reflected the
source state before all those DELTA enum's were added.
[ plus add a couple of overlooked #undef directives, ]
[ and whack an unneeded stacks_alloc assignment too! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
This interface represented a 2nd generation attempt at
the opaque newlib approach. In other words, it did not
involve the 1st generation 'chains'. Instead, 'stacks'
were employed. But the interface wasn't user friendly.
Users were required to create their own stacks, before
calling 'getstack' to retrieve multiple results with a
single call. Even worse, sometimes 'read' was required
before calling 'get' when working with single results.
So this commit represents the 3rd generation approach.
We eliminate the burden of 'read' and creating stacks.
Rather, beyond those standard 'new', 'ref' and 'unref'
functions, we'll offer just 'get' (single result) plus
a 'select' function (for multiple results in 1 stack).
And along the way, this commit vastly expands the data
extracted from /proc/vmstat. All values that currently
exist (and their delta equivalents) are now available.
Deltas were included for everything because there's no
real runtime costs beyond using a little extra memory.
The only problem is a lack of documentation for all of
those fields, as is reflected in the references below.
Oh well, maybe someday someone will dig through kernel
sources & finally plug that rather large document gap.
[ as an aside, rather than using a 'strcmp' approach ]
[ when parsing the /proc/vmstat file, as is found in ]
[ the <meminfo> module, we exploit those hash search ]
[ provisions that are found in the <search.h> header ]
Reference(s):
http://www.spinics.net/lists/linux-man/msg09096.htmlhttp://www.linuxinsight.com/proc_vmstat.html
Signed-off-by: Jim Warner <james.warner@comcast.net>
In addition to that text shown below the line which is
common to several commit messages, this patch contains
several minor changes with lessor impact upon the API:
. Standard copyright boilerplate was added in .c file.
. The #include header files are ordered alphabetically
now, with all those <sys/??> types separately grouped.
. The header file follows the conventions of indenting
(by 4 spaces) those parameters too lengthy for 1 line.
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. The former 'chains' have now become 'stacks' without
the 'next' pointer in each result struct. The pointers
initially seemed to offer some flexibility with memory
allocations and benefits for the library access logic.
However, user access was always via displacement and a
a statically allocated chain was cumbersome to define.
. An enumerator ending in '_noop' will no longer serve
as a fencepost delimiter. Rather, it has become a much
more important and flexible user oriented tool. Adding
one or more such 'items' in any items list passed into
the library becomes the means of extending the 'stack'
to also include user (not just library) data. Any such
data is guaranteed to never be altered by the library.
. Anticipating PID support, where many different types
must be represented in a result structure, we'll adopt
a common naming standard. And, while not every results
structure currently needs to reflect disparate types a
union will be employed so the same dot qualifier ('.')
can be used consistently when accessing all such data.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The earlier attempt at protecting these functions from
already freed memory worked just fine until the memory
was, in fact, reused by the OS. At that point, the ref
count would most likely fail an existing a test for 0.
So this commit will take control of the 'info' pointer
and force it to NULL when a reference count reaches 0.
Plus, since it makes little sense returning an address
that a caller already has, henceforth we will return a
reference count out of the 'ref' and 'unref functions.
Reference(s):
commit 74beff80ff
Signed-off-by: Jim Warner <james.warner@comcast.net>
Since we are not using a higher level standard C fopen
all of the read requests were made signal sensitive as
that can result in a 'temporarily' failed i/o request.
Also, protection against some user calling the 'unref'
function on already free memory has been incorporated.
This will protect us from some nasty 'Abort' surprise.
Signed-off-by: Jim Warner <james.warner@comcast.net>
If a caller chooses to reduce the overhead of repeated
function calls, this commit provides for acquiring all
the desired information in just a single library call.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch mostly just eliminates darn tab characters.
Plus the library function declarations and definitions
have been standardized. Most visibly, the input params
now have all been indented on their own separate line.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Created new set of functions for meminfo related calls. Liked the
format of that better so changed vmstat around so the look similar.
Missed the makefile change for uptime so added it in now.
Use the standard libc declarations.
For protecting the headers for C++ procps used to have its
own defines, this change makes them use the standard libc ones.
getstat() -> procps_stat_*
vminfo() -> procps_vmstat_*
These two components of the library now use the newer version of
the API with less exposed global variables. The old methods are
there for now.
Signed-off-by: Craig Small <csmall@enc.com.au>
