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[Libvir] remove global variables from header files



Hello,

I compiled the latest-from-cvs libvirt and was surprised to
see link failures.  It was because I used -fno-common:

  .libs/libvirt_la-hash.o:(.bss+0x0): multiple definition of `virDomainFlags'
  .libs/libvirt_la-libvirt.o:(.bss+0x0): first defined here

  libvirt_qemud-buf.o:(.bss+0x0): multiple definition of `qemud_packet_type'
  libvirt_qemud-qemud.o:(.bss+0x0): first defined here
  libvirt_qemud-buf.o:(.bss+0x4): multiple definition of `qemud_domain_runstate'
  libvirt_qemud-qemud.o:(.bss+0x4): first defined here

Those happen when more than one compilation unit contains a non-extern
declaration of the same global variable.

In each of the three cases, the name in question appears only
at the point of declaration, so one could conceivably simply
remove the name, leaving the anonymous "enum".  But then there
would be no way to declare a variable to be of that type, so
I chose to reuse the name, making it the name of the enum.
If name space pollution is an issue, and applications that use
those headers won't need those types, then it'd be better to
remove the names altogether.

Here's a patch:

2007-03-19  Jim Meyering  <jim meyering net>

	Remove global variables from header files.
	* qemud/protocol.h (qemud_domain_runstate): Declare a named enum and
	no variable, rather than a global variable of type "anonymous enum".
	(qemud_packet_type): Likewise.
	* src/internal.h (virDomainFlags): Likewise.

Index: qemud/protocol.h
===================================================================
RCS file: /data/cvs/libvirt/qemud/protocol.h,v
retrieving revision 1.5
diff -u -p -r1.5 protocol.h
--- qemud/protocol.h	15 Mar 2007 17:24:57 -0000	1.5
+++ qemud/protocol.h	19 Mar 2007 13:36:55 -0000
@@ -29,7 +29,7 @@
 #include <net/if.h> /* for IF_NAMESIZE */

 /* List of different packet types which can be sent */
-enum {
+enum qemud_packet_type {
     QEMUD_PKT_FAILURE = 0,
     QEMUD_PKT_GET_VERSION,
     QEMUD_PKT_GET_NODEINFO,
@@ -71,7 +71,7 @@ enum {
     QEMUD_PKT_GET_CAPABILITIES,

     QEMUD_PKT_MAX,
-} qemud_packet_type;
+};


 #define QEMUD_PROTOCOL_VERSION_MAJOR 1
@@ -86,11 +86,11 @@ enum {
 #define QEMUD_MAX_ERROR_LEN 1024

 /* Possible guest VM states */
-enum {
+enum qemud_domain_runstate {
     QEMUD_STATE_RUNNING = 1,
     QEMUD_STATE_PAUSED,
     QEMUD_STATE_STOPPED,
-} qemud_domain_runstate;
+};

 /* Each packets has at least a fixed size header.
  *
Index: src/internal.h
===================================================================
RCS file: /data/cvs/libvirt/src/internal.h,v
retrieving revision 1.35
diff -u -p -r1.35 internal.h
--- src/internal.h	16 Mar 2007 15:03:21 -0000	1.35
+++ src/internal.h	19 Mar 2007 13:36:55 -0000
@@ -155,10 +155,10 @@ struct _virConnect {
 * a set of special flag values associated to the domain
 */

-enum {
+enum virDomainFlags {
     DOMAIN_IS_SHUTDOWN = (1 << 0),  /* the domain is being shutdown */
     DOMAIN_IS_DEFINED  = (1 << 1)   /* the domain is defined not running */
-} virDomainFlags;
+};

 /**
 * _virDomain:


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