Re: [libvirt] [PATCH 2/7] Add accessors for logging filters and outputs

Daniel P. Berrange wrote: [Tue Oct 06 2009, 05:00:55AM EDT] That makes sense. Does this look good now? --- When configuring logging settings, keep more information about the output destination. Add accessors to retrieve the filter and output settings in the original string form; this to be used to set up environment for a child process that also logs. Open output files O_APPEND so child can also write -- was there a reason to truncate them? Note this patch changes the API for virLogDefineOutput(), which is part of the internal libvirt API, but is currently only used within logging.c. --- src/libvirt_private.syms | 2 + src/util/logging.c | 112 +++++++++++++++++++++++++++++++++++++++++++--- src/util/logging.h | 14 +++++- 3 files changed, 119 insertions(+), 9 deletions(-) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index fb9b9ae..732fd08 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -253,6 +253,8 @@ virRegisterSecretDriver; virLogMessage; virLogGetNbFilters; virLogGetNbOutputs; +virLogGetFilters; +virLogGetOutputs; virLogGetDefaultPriority; virLogSetDefaultPriority; virLogSetFromEnv; diff --git a/src/util/logging.c b/src/util/logging.c index 07c2b0e..4899de6 100644 --- a/src/util/logging.c +++ b/src/util/logging.c @@ -37,6 +37,7 @@ #include "logging.h" #include "memory.h" #include "util.h" +#include "buf.h" #include "threads.h" /* @@ -109,6 +110,8 @@ struct _virLogOutput { virLogOutputFunc f; virLogCloseFunc c; int priority; + virLogDestination dest; + const char *name; }; typedef struct _virLogOutput virLogOutput; typedef virLogOutput *virLogOutputPtr; @@ -138,6 +141,17 @@ static void virLogUnlock(void) virMutexUnlock(&virLogMutex); } +static const char *virLogOutputString(virLogDestination ldest) { + switch (ldest) { + case VIR_LOG_TO_STDERR: + return("stderr"); + case VIR_LOG_TO_SYSLOG: + return("syslog"); + case VIR_LOG_TO_FILE: + return("file"); + } + return("unknown"); +} static const char *virLogPriorityString(virLogPriority lvl) { switch (lvl) { @@ -428,6 +442,7 @@ static int virLogResetOutputs(void) { for (i = 0;i < virLogNbOutputs;i++) { if (virLogOutputs[i].c != NULL) virLogOutputs[i].c(virLogOutputs[i].data); + VIR_FREE(virLogOutputs[i].name); } VIR_FREE(virLogOutputs); i = virLogNbOutputs; @@ -438,9 +453,11 @@ static int virLogResetOutputs(void) { /** * virLogDefineOutput: * @f: the function to call to output a message - * @f: the function to call to close the output (or NULL) + * @c: the function to call to close the output (or NULL) * @data: extra data passed as first arg to the function * @priority: minimal priority for this filter, use 0 for none + * @dest: where to send output of this priority + * @name: optional name data associated with an output * @flags: extra flag, currently unused * * Defines an output function for log messages. Each message once @@ -449,12 +466,22 @@ static int virLogResetOutputs(void) { * Returns -1 in case of failure or the output number if successful */ int virLogDefineOutput(virLogOutputFunc f, virLogCloseFunc c, void *data, - int priority, int flags ATTRIBUTE_UNUSED) { + int priority, int dest, const char *name, + int flags ATTRIBUTE_UNUSED) { int ret = -1; + char *ndup = NULL; if (f == NULL) return(-1); + if (dest == VIR_LOG_TO_SYSLOG || dest == VIR_LOG_TO_FILE) { + if (name == NULL) + return(-1); + ndup = strdup(name); + if (ndup == NULL) + return(-1); + } + virLogLock(); if (VIR_REALLOC_N(virLogOutputs, virLogNbOutputs + 1)) { goto cleanup; @@ -464,6 +491,8 @@ int virLogDefineOutput(virLogOutputFunc f, virLogCloseFunc c, void *data, virLogOutputs[ret].c = c; virLogOutputs[ret].data = data; virLogOutputs[ret].priority = priority; + virLogOutputs[ret].dest = dest; + virLogOutputs[ret].name = ndup; cleanup: virLogUnlock(); return(ret); @@ -577,7 +606,8 @@ static void virLogCloseFd(void *data) { } static int virLogAddOutputToStderr(int priority) { - if (virLogDefineOutput(virLogOutputToFd, NULL, (void *)2L, priority, 0) < 0) + if (virLogDefineOutput(virLogOutputToFd, NULL, (void *)2L, priority, + VIR_LOG_TO_STDERR, NULL, 0) < 0) return(-1); return(0); } @@ -585,11 +615,11 @@ static int virLogAddOutputToStderr(int priority) { static int virLogAddOutputToFile(int priority, const char *file) { int fd; - fd = open(file, O_CREAT | O_TRUNC | O_WRONLY, S_IRUSR | S_IWUSR); + fd = open(file, O_CREAT | O_APPEND | O_WRONLY, S_IRUSR | S_IWUSR); if (fd < 0) return(-1); if (virLogDefineOutput(virLogOutputToFd, virLogCloseFd, (void *)(long)fd, - priority, 0) < 0) { + priority, VIR_LOG_TO_FILE, file, 0) < 0) { close(fd); return(-1); } @@ -643,7 +673,7 @@ static int virLogAddOutputToSyslog(int priority, const char *ident) { openlog(current_ident, 0, 0); if (virLogDefineOutput(virLogOutputToSyslog, virLogCloseSyslog, NULL, - priority, 0) < 0) { + priority, VIR_LOG_TO_SYSLOG, ident, 0) < 0) { closelog(); VIR_FREE(current_ident); return(-1); @@ -682,6 +712,7 @@ static int virLogAddOutputToSyslog(int priority, const char *ident) { int virLogParseOutputs(const char *outputs) { const char *cur = outputs, *str; char *name; + char *abspath; int prio; int ret = -1; int count = 0; @@ -732,9 +763,14 @@ int virLogParseOutputs(const char *outputs) { name = strndup(str, cur - str); if (name == NULL) goto cleanup; - if (virLogAddOutputToFile(prio, name) == 0) + if (virFileAbsPath(name, &abspath) < 0) { + VIR_FREE(name); + return -1; /* skip warning here because setting was fine */ + } + if (virLogAddOutputToFile(prio, abspath) == 0) count++; VIR_FREE(name); + VIR_FREE(abspath); } else { goto cleanup; } @@ -813,6 +849,68 @@ int virLogGetDefaultPriority(void) { } /** + * virLogGetFilters: + * + * Returns a string listing the current filters, in the format originally + * specified in the config file or environment. Caller must free the + * result. + */ +char *virLogGetFilters(void) { + int i; + virBuffer filterbuf = VIR_BUFFER_INITIALIZER; + + virLogLock(); + for (i = 0; i < virLogNbFilters; i++) { + virBufferVSprintf(&filterbuf, "%d:%s ", virLogFilters[i].priority, + virLogFilters[i].match); + } + virLogUnlock(); + + if (virBufferError(&filterbuf)) + return NULL; + + return virBufferContentAndReset(&filterbuf); +} + +/** + * virLogGetOutputs: + * + * Returns a string listing the current outputs, in the format originally + * specified in the config file or environment. Caller must free the + * result. + */ +char *virLogGetOutputs(void) { + int i; + virBuffer outputbuf = VIR_BUFFER_INITIALIZER; + + virLogLock(); + for (i = 0; i < virLogNbOutputs; i++) { + int dest = virLogOutputs[i].dest; + if (i) + virBufferVSprintf(&outputbuf, " "); + switch (dest) { + case VIR_LOG_TO_SYSLOG: + case VIR_LOG_TO_FILE: + virBufferVSprintf(&outputbuf, "%d:%s:%s", + virLogOutputs[i].priority, + virLogOutputString(dest), + virLogOutputs[i].name); + break; + default: + virBufferVSprintf(&outputbuf, "%d:%s", + virLogOutputs[i].priority, + virLogOutputString(dest)); + } + } + virLogUnlock(); + + if (virBufferError(&outputbuf)) + return NULL; + + return virBufferContentAndReset(&outputbuf); +} + +/** * virLogGetNbFilters: * * Returns the current number of defined log filters. diff --git a/src/util/logging.h b/src/util/logging.h index 8b2b84c..49e2f6d 100644 --- a/src/util/logging.h +++ b/src/util/logging.h @@ -23,6 +23,7 @@ #define __VIRTLOG_H_ #include "internal.h" +#include "buf.h" /* * If configured with --enable-debug=yes then library calls @@ -79,6 +80,12 @@ typedef enum { #define VIR_LOG_DEFAULT VIR_LOG_WARN +typedef enum { + VIR_LOG_TO_STDERR = 1, + VIR_LOG_TO_SYSLOG, + VIR_LOG_TO_FILE, +} virLogDestination; + /** * virLogOutputFunc: * @category: the category for the message @@ -107,12 +114,15 @@ typedef void (*virLogCloseFunc) (void *data); extern int virLogGetNbFilters(void); extern int virLogGetNbOutputs(void); +extern char *virLogGetFilters(void); +extern char *virLogGetOutputs(void); extern int virLogGetDefaultPriority(void); extern int virLogSetDefaultPriority(int priority); extern void virLogSetFromEnv(void); extern int virLogDefineFilter(const char *match, int priority, int flags); -extern int virLogDefineOutput(virLogOutputFunc f, virLogCloseFunc c, - void *data, int priority, int flags); +extern int virLogDefineOutput(virLogOutputFunc f, virLogCloseFunc c, void *data, + int priority, int dest, const char *name, + int flags); /* * Internal logging API