libvirt/src/util/conf.c
Daniel P. Berrange 777ffbd0e2 Allow for URI aliases when connecting to libvirt
This adds support for a libvirt client configuration file
either /etc/libvirt/libvirt.conf for privileged clients,
or $HOME/.libvirt/libvirt.conf for unprivileged clients.

It allows one parameter

 uri_aliases = [
   "hail=qemu+ssh://root@hail.cloud.example.com/system",
   "sleet=qemu+ssh://root@sleet.cloud.example.com/system",
 ]

Any call to virConnectOpen with a non-NULL URI will first
attempt to match against the uri_aliases list. An application
can disable this by using VIR_CONNECT_NO_ALIASES

* docs/uri.html.in: Document URI aliases
* include/libvirt/libvirt.h.in: Add VIR_CONNECT_NO_ALIASES
* libvirt.spec.in, mingw32-libvirt.spec.in: Add /etc/libvirt/libvirt.conf
* src/Makefile.am: Install default config file
* src/libvirt.c: Add support for URI aliases
* src/remote/remote_driver.c: Don't try to handle URIs
  with no scheme and which clearly are not paths
* src/util/conf.c: Don't raise error on virConfFree(NULL)
* src/xen/xen_driver.c: Don't raise error on URIs
  with no scheme
2011-10-19 09:14:34 +01:00

1019 lines
25 KiB
C

/**
* conf.c: parser for a subset of the Python encoded Xen configuration files
*
* Copyright (C) 2006-2011 Red Hat, Inc.
*
* See COPYING.LIB for the License of this software
*
* Daniel Veillard <veillard@redhat.com>
*/
#include <config.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "virterror_internal.h"
#include "buf.h"
#include "conf.h"
#include "util.h"
#include "c-ctype.h"
#include "memory.h"
#include "virfile.h"
#define VIR_FROM_THIS VIR_FROM_CONF
/************************************************************************
* *
* Structures and macros used by the mini parser *
* *
************************************************************************/
typedef struct _virConfParserCtxt virConfParserCtxt;
typedef virConfParserCtxt *virConfParserCtxtPtr;
struct _virConfParserCtxt {
const char* filename;
const char* base;
const char* cur;
const char *end;
int line;
virConfPtr conf;
};
#define CUR (*ctxt->cur)
#define NEXT if (ctxt->cur < ctxt->end) ctxt->cur++;
#define IS_EOL(c) (((c) == '\n') || ((c) == '\r'))
#define SKIP_BLANKS_AND_EOL \
do { while ((ctxt->cur < ctxt->end) && (c_isblank(CUR) || IS_EOL(CUR))) { \
if (CUR == '\n') ctxt->line++; \
ctxt->cur++;}} while (0)
#define SKIP_BLANKS \
do { while ((ctxt->cur < ctxt->end) && (c_isblank(CUR))) \
ctxt->cur++; } while (0)
/************************************************************************
* *
* Structures used by configuration data *
* *
************************************************************************/
typedef struct _virConfEntry virConfEntry;
typedef virConfEntry *virConfEntryPtr;
struct _virConfEntry {
virConfEntryPtr next;
char* name;
char* comment;
virConfValuePtr value;
};
struct _virConf {
const char* filename;
unsigned int flags;
virConfEntryPtr entries;
};
/**
* virConfError:
* @ctxt: the parser context if available or NULL
* @error: the error number
* @info: extra information string
*
* Handle an error at the xend daemon interface
*/
static void
virConfError(virConfParserCtxtPtr ctxt,
virErrorNumber error, const char *info)
{
const char *format;
if (error == VIR_ERR_OK)
return;
/* Construct the string 'filename:line: info' if we have that. */
if (ctxt && ctxt->filename) {
virRaiseError(NULL, NULL, VIR_FROM_CONF, error, VIR_ERR_ERROR,
info, ctxt->filename, NULL,
ctxt->line, 0,
"%s:%d: %s", ctxt->filename, ctxt->line, info);
} else {
format = virErrorMsg(error, info);
virRaiseError(NULL, NULL, VIR_FROM_CONF, error, VIR_ERR_ERROR,
info, NULL, NULL,
ctxt ? ctxt->line : 0, 0,
format, info);
}
}
/************************************************************************
* *
* Structures allocations and deallocations *
* *
************************************************************************/
/**
* virConfFreeList:
* @list: the list to free
*
* Free a list
*/
static void
virConfFreeList(virConfValuePtr list)
{
virConfValuePtr next;
while (list != NULL) {
next = list->next;
list->next = NULL;
virConfFreeValue(list);
list = next;
}
}
/**
* virConfFreeValue:
* @val: the value to free
*
* Free a value
*/
void
virConfFreeValue(virConfValuePtr val)
{
if (val == NULL)
return;
if (val->type == VIR_CONF_STRING &&
val->str != NULL)
VIR_FREE(val->str);
if (val->type == VIR_CONF_LIST &&
val->list != NULL)
virConfFreeList(val->list);
VIR_FREE(val);
}
virConfPtr
virConfNew(void)
{
virConfPtr ret;
if (VIR_ALLOC(ret) < 0) {
virReportOOMError();
return(NULL);
}
ret->filename = NULL;
ret->flags = 0;
return(ret);
}
/**
* virConfCreate:
* @filename: the name to report errors
* @flags: combination of virConfFlag(s)
*
* Create a configuration internal structure
*
* Returns a pointer or NULL in case of error.
*/
static virConfPtr
virConfCreate(const char *filename, unsigned int flags)
{
virConfPtr ret = virConfNew();
if (ret) {
ret->filename = filename;
ret->flags = flags;
}
return(ret);
}
/**
* virConfAddEntry:
* @conf: the conf structure
* @name: name of the entry or NULL for comment
* @value: the value if any
* @comm: extra comment for that entry if any
*
* add one entry to the conf, the parameters are included in the conf
* if successful and freed on virConfFree()
*
* Returns a pointer to the entry or NULL in case of failure
*/
static virConfEntryPtr
virConfAddEntry(virConfPtr conf, char *name, virConfValuePtr value, char *comm)
{
virConfEntryPtr ret, prev;
if (conf == NULL)
return(NULL);
if ((comm == NULL) && (name == NULL))
return(NULL);
if (VIR_ALLOC(ret) < 0) {
virReportOOMError();
return(NULL);
}
ret->name = name;
ret->value = value;
ret->comment = comm;
if (conf->entries == NULL) {
conf->entries = ret;
} else {
prev = conf->entries;
while (prev->next != NULL)
prev = prev->next;
prev->next = ret;
}
return(ret);
}
/************************************************************************
* *
* Serialization *
* *
************************************************************************/
/**
* virConfSaveValue:
* @buf: output buffer
* @val: a value
*
* Serialize the value to the buffer
*
* Returns 0 in case of success, -1 in case of error.
*/
static int
virConfSaveValue(virBufferPtr buf, virConfValuePtr val)
{
if (val == NULL)
return(-1);
switch (val->type) {
case VIR_CONF_NONE:
return(-1);
case VIR_CONF_LONG:
virBufferAsprintf(buf, "%ld", val->l);
break;
case VIR_CONF_STRING:
if (strchr(val->str, '\n') != NULL) {
virBufferAsprintf(buf, "\"\"\"%s\"\"\"", val->str);
} else if (strchr(val->str, '"') == NULL) {
virBufferAsprintf(buf, "\"%s\"", val->str);
} else if (strchr(val->str, '\'') == NULL) {
virBufferAsprintf(buf, "'%s'", val->str);
} else {
virBufferAsprintf(buf, "\"\"\"%s\"\"\"", val->str);
}
break;
case VIR_CONF_LIST: {
virConfValuePtr cur;
cur = val->list;
virBufferAddLit(buf, "[ ");
if (cur != NULL) {
virConfSaveValue(buf, cur);
cur = cur->next;
while (cur != NULL) {
virBufferAddLit(buf, ", ");
virConfSaveValue(buf, cur);
cur = cur->next;
}
}
virBufferAddLit(buf, " ]");
break;
}
default:
return(-1);
}
return(0);
}
/**
* virConfSaveEntry:
* @buf: output buffer
* @cur: a conf entry
*
* Serialize the entry to the buffer
*
* Returns 0 in case of success, -1 in case of error.
*/
static int
virConfSaveEntry(virBufferPtr buf, virConfEntryPtr cur)
{
if (cur->name != NULL) {
virBufferAdd(buf, cur->name, -1);
virBufferAddLit(buf, " = ");
virConfSaveValue(buf, cur->value);
if (cur->comment != NULL) {
virBufferAddLit(buf, " #");
virBufferAdd(buf, cur->comment, -1);
}
} else if (cur->comment != NULL) {
virBufferAddLit(buf, "#");
virBufferAdd(buf, cur->comment, -1);
}
virBufferAddLit(buf, "\n");
return(0);
}
/************************************************************************
* *
* The parser core *
* *
************************************************************************/
/**
* virConfParseLong:
* @ctxt: the parsing context
* @val: the result
*
* Parse one long int value
*
* Returns 0 in case of success and -1 in case of error
*/
static int
virConfParseLong(virConfParserCtxtPtr ctxt, long *val)
{
long l = 0;
int neg = 0;
if (CUR == '-') {
neg = 1;
NEXT;
} else if (CUR == '+') {
NEXT;
}
if ((ctxt->cur >= ctxt->end) || (!c_isdigit(CUR))) {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("unterminated number"));
return(-1);
}
while ((ctxt->cur < ctxt->end) && (c_isdigit(CUR))) {
l = l * 10 + (CUR - '0');
NEXT;
}
if (neg)
l = -l;
*val = l;
return(0);
}
/**
* virConfParseString:
* @ctxt: the parsing context
*
* Parse one string
*
* Returns a pointer to the string or NULL in case of error
*/
static char *
virConfParseString(virConfParserCtxtPtr ctxt)
{
const char *base;
char *ret = NULL;
if (CUR == '\'') {
NEXT;
base = ctxt->cur;
while ((ctxt->cur < ctxt->end) && (CUR != '\'') && (!IS_EOL(CUR)))
NEXT;
if (CUR != '\'') {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("unterminated string"));
return(NULL);
}
ret = strndup(base, ctxt->cur - base);
if (ret == NULL) {
virReportOOMError();
return NULL;
}
NEXT;
} else if ((ctxt->cur + 6 < ctxt->end) &&
(STRPREFIX(ctxt->cur, "\"\"\""))) {
/* String starts with python-style triple quotes """ */
ctxt->cur += 3;
base = ctxt->cur;
/* Find the ending triple quotes */
while ((ctxt->cur + 2 < ctxt->end) &&
!(STRPREFIX(ctxt->cur, "\"\"\""))) {
if (CUR == '\n')
ctxt->line++;
NEXT;
}
if (!STRPREFIX(ctxt->cur, "\"\"\"")) {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("unterminated string"));
return(NULL);
}
ret = strndup(base, ctxt->cur - base);
if (ret == NULL) {
virReportOOMError();
return NULL;
}
ctxt->cur += 3;
} else if (CUR == '"') {
NEXT;
base = ctxt->cur;
while ((ctxt->cur < ctxt->end) && (CUR != '"') && (!IS_EOL(CUR)))
NEXT;
if (CUR != '"') {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("unterminated string"));
return(NULL);
}
ret = strndup(base, ctxt->cur - base);
if (ret == NULL) {
virReportOOMError();
return NULL;
}
NEXT;
}
return(ret);
}
/**
* virConfParseValue:
* @ctxt: the parsing context
*
* Parse one value
*
* Returns a pointer to the value or NULL in case of error
*/
static virConfValuePtr
virConfParseValue(virConfParserCtxtPtr ctxt)
{
virConfValuePtr ret, lst = NULL, tmp, prev;
virConfType type = VIR_CONF_NONE;
char *str = NULL;
long l = 0;
SKIP_BLANKS;
if (ctxt->cur >= ctxt->end) {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("expecting a value"));
return(NULL);
}
if ((CUR == '"') || (CUR == '\'')) {
type = VIR_CONF_STRING;
str = virConfParseString(ctxt);
if (str == NULL)
return(NULL);
} else if (CUR == '[') {
if (ctxt->conf->flags & VIR_CONF_FLAG_VMX_FORMAT) {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX,
_("lists not allowed in VMX format"));
return(NULL);
}
type = VIR_CONF_LIST;
NEXT;
SKIP_BLANKS_AND_EOL;
if ((ctxt->cur < ctxt->end) && (CUR != ']')) {
if ((lst = virConfParseValue(ctxt)) == NULL)
return(NULL);
SKIP_BLANKS_AND_EOL;
}
while ((ctxt->cur < ctxt->end) && (CUR != ']')) {
/* Tell Clang that when execution reaches this point
"lst" is guaranteed to be non-NULL. This stops it
from issuing an invalid NULL-dereference warning about
"prev = lst; while (prev->next..." below. */
sa_assert (lst);
if (CUR != ',') {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX,
_("expecting a separator in list"));
virConfFreeList(lst);
return(NULL);
}
NEXT;
SKIP_BLANKS_AND_EOL;
if (CUR == ']') {
break;
}
tmp = virConfParseValue(ctxt);
if (tmp == NULL) {
virConfFreeList(lst);
return(NULL);
}
prev = lst;
while (prev->next != NULL) prev = prev->next;
prev->next = tmp;
SKIP_BLANKS_AND_EOL;
}
if (CUR == ']') {
NEXT;
} else {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX,
_("list is not closed with ]"));
virConfFreeList(lst);
return(NULL);
}
} else if (c_isdigit(CUR) || (CUR == '-') || (CUR == '+')) {
if (ctxt->conf->flags & VIR_CONF_FLAG_VMX_FORMAT) {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX,
_("numbers not allowed in VMX format"));
return(NULL);
}
if (virConfParseLong(ctxt, &l) < 0) {
return(NULL);
}
type = VIR_CONF_LONG;
} else {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("expecting a value"));
return(NULL);
}
if (VIR_ALLOC(ret) < 0) {
virReportOOMError();
virConfFreeList(lst);
VIR_FREE(str);
return(NULL);
}
ret->type = type;
ret->l = l;
ret->str = str;
ret->list = lst;
return(ret);
}
/**
* virConfParseName:
* @ctxt: the parsing context
*
* Parse one name
*
* Returns a copy of the new string, NULL in case of error
*/
static char *
virConfParseName(virConfParserCtxtPtr ctxt)
{
const char *base;
char *ret;
SKIP_BLANKS;
base = ctxt->cur;
/* TODO: probably need encoding support and UTF-8 parsing ! */
if (!c_isalpha(CUR) &&
!((ctxt->conf->flags & VIR_CONF_FLAG_VMX_FORMAT) && (CUR == '.'))) {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("expecting a name"));
return(NULL);
}
while ((ctxt->cur < ctxt->end) &&
(c_isalnum(CUR) || (CUR == '_') ||
((ctxt->conf->flags & VIR_CONF_FLAG_VMX_FORMAT) &&
((CUR == ':') || (CUR == '.') || (CUR == '-')))))
NEXT;
ret = strndup(base, ctxt->cur - base);
if (ret == NULL) {
virReportOOMError();
return(NULL);
}
return(ret);
}
/**
* virConfParseComment:
* @ctxt: the parsing context
*
* Parse one standalone comment in the configuration file
*
* Returns 0 in case of success and -1 in case of error
*/
static int
virConfParseComment(virConfParserCtxtPtr ctxt)
{
const char *base;
char *comm;
if (CUR != '#')
return(-1);
NEXT;
base = ctxt->cur;
while ((ctxt->cur < ctxt->end) && (!IS_EOL(CUR))) NEXT;
comm = strndup(base, ctxt->cur - base);
if (comm == NULL) {
virReportOOMError();
return(-1);
}
virConfAddEntry(ctxt->conf, NULL, NULL, comm);
return(0);
}
/**
* virConfParseSeparator:
* @ctxt: the parsing context
*
* Parse one separator between statement if not at the end.
*
* Returns 0 in case of success and -1 in case of error
*/
static int
virConfParseSeparator(virConfParserCtxtPtr ctxt)
{
SKIP_BLANKS;
if (ctxt->cur >= ctxt->end)
return(0);
if (IS_EOL(CUR)) {
SKIP_BLANKS_AND_EOL;
} else if (CUR == ';') {
NEXT;
SKIP_BLANKS_AND_EOL;
} else {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("expecting a separator"));
return(-1);
}
return(0);
}
/**
* virConfParseStatement:
* @ctxt: the parsing context
*
* Parse one statement in the conf file
*
* Returns 0 in case of success and -1 in case of error
*/
static int
virConfParseStatement(virConfParserCtxtPtr ctxt)
{
const char *base;
char *name;
virConfValuePtr value;
char *comm = NULL;
SKIP_BLANKS_AND_EOL;
if (CUR == '#') {
return virConfParseComment(ctxt);
}
name = virConfParseName(ctxt);
if (name == NULL)
return -1;
SKIP_BLANKS;
if (CUR != '=') {
virConfError(ctxt, VIR_ERR_CONF_SYNTAX, _("expecting an assignment"));
VIR_FREE(name);
return -1;
}
NEXT;
SKIP_BLANKS;
value = virConfParseValue(ctxt);
if (value == NULL) {
VIR_FREE(name);
return -1;
}
SKIP_BLANKS;
if (CUR == '#') {
NEXT;
base = ctxt->cur;
while ((ctxt->cur < ctxt->end) && (!IS_EOL(CUR))) NEXT;
comm = strndup(base, ctxt->cur - base);
if (comm == NULL) {
virReportOOMError();
VIR_FREE(name);
virConfFreeValue(value);
return -1;
}
}
if (virConfAddEntry(ctxt->conf, name, value, comm) == NULL) {
VIR_FREE(name);
virConfFreeValue(value);
VIR_FREE(comm);
return -1;
}
return 0;
}
/**
* virConfParse:
* @filename: the name to report errors
* @content: the configuration content in memory
* @len: the length in bytes
* @flags: combination of virConfFlag(s)
*
* Parse the subset of the Python language needed to handle simple
* Xen configuration files.
*
* Returns an handle to lookup settings or NULL if it failed to
* read or parse the file, use virConfFree() to free the data.
*/
static virConfPtr
virConfParse(const char *filename, const char *content, int len,
unsigned int flags) {
virConfParserCtxt ctxt;
ctxt.filename = filename;
ctxt.base = ctxt.cur = content;
ctxt.end = content + len - 1;
ctxt.line = 1;
ctxt.conf = virConfCreate(filename, flags);
if (ctxt.conf == NULL)
return(NULL);
while (ctxt.cur < ctxt.end) {
if (virConfParseStatement(&ctxt) < 0)
goto error;
if (virConfParseSeparator(&ctxt) < 0)
goto error;
}
return(ctxt.conf);
error:
virConfFree(ctxt.conf);
return(NULL);
}
/************************************************************************
* *
* The module entry points *
* *
************************************************************************/
/* 10 MB limit on config file size as a sanity check */
#define MAX_CONFIG_FILE_SIZE (1024*1024*10)
/**
* virConfReadFile:
* @filename: the path to the configuration file.
* @flags: combination of virConfFlag(s)
*
* Reads a configuration file.
*
* Returns an handle to lookup settings or NULL if it failed to
* read or parse the file, use virConfFree() to free the data.
*/
virConfPtr
virConfReadFile(const char *filename, unsigned int flags)
{
char *content;
int len;
virConfPtr conf;
if (filename == NULL) {
virConfError(NULL, VIR_ERR_INVALID_ARG, __FUNCTION__);
return(NULL);
}
if ((len = virFileReadAll(filename, MAX_CONFIG_FILE_SIZE, &content)) < 0) {
return NULL;
}
conf = virConfParse(filename, content, len, flags);
VIR_FREE(content);
return conf;
}
/**
* virConfReadMem:
* @memory: pointer to the content of the configuration file
* @len: length in byte
* @flags: combination of virConfFlag(s)
*
* Reads a configuration file loaded in memory. The string can be
* zero terminated in which case @len can be 0
*
* Returns an handle to lookup settings or NULL if it failed to
* parse the content, use virConfFree() to free the data.
*/
virConfPtr
virConfReadMem(const char *memory, int len, unsigned int flags)
{
if ((memory == NULL) || (len < 0)) {
virConfError(NULL, VIR_ERR_INVALID_ARG, __FUNCTION__);
return(NULL);
}
if (len == 0)
len = strlen(memory);
return(virConfParse("memory conf", memory, len, flags));
}
/**
* virConfFree:
* @conf: a configuration file handle
*
* Frees all data associated to the handle
*
* Returns 0 in case of success, -1 in case of error.
*/
int
virConfFree(virConfPtr conf)
{
virConfEntryPtr tmp;
if (conf == NULL)
return 0;
tmp = conf->entries;
while (tmp) {
virConfEntryPtr next;
VIR_FREE(tmp->name);
virConfFreeValue(tmp->value);
VIR_FREE(tmp->comment);
next = tmp->next;
VIR_FREE(tmp);
tmp = next;
}
VIR_FREE(conf);
return(0);
}
/**
* virConfGetValue:
* @conf: a configuration file handle
* @entry: the name of the entry
*
* Lookup the value associated to this entry in the configuration file
*
* Returns a pointer to the value or NULL if the lookup failed, the data
* associated will be freed when virConfFree() is called
*/
virConfValuePtr
virConfGetValue(virConfPtr conf, const char *setting)
{
virConfEntryPtr cur;
cur = conf->entries;
while (cur != NULL) {
if ((cur->name != NULL) &&
((conf->flags & VIR_CONF_FLAG_VMX_FORMAT &&
STRCASEEQ(cur->name, setting)) ||
STREQ(cur->name, setting)))
return(cur->value);
cur = cur->next;
}
return(NULL);
}
/**
* virConfSetValue:
* @conf: a configuration file handle
* @entry: the name of the entry
* @value: the new configuration value
*
* Set (or replace) the value associated to this entry in the configuration
* file. The passed in 'value' will be owned by the conf object upon return
* of this method, even in case of error. It should not be referenced again
* by the caller.
*
* Returns 0 on success, or -1 on failure.
*/
int
virConfSetValue (virConfPtr conf,
const char *setting,
virConfValuePtr value)
{
virConfEntryPtr cur, prev = NULL;
if (value && value->type == VIR_CONF_STRING && value->str == NULL)
return -1;
cur = conf->entries;
while (cur != NULL) {
if ((cur->name != NULL) && (STREQ(cur->name, setting))) {
break;
}
prev = cur;
cur = cur->next;
}
if (!cur) {
if (VIR_ALLOC(cur) < 0) {
virReportOOMError();
virConfFreeValue(value);
return (-1);
}
cur->comment = NULL;
if (!(cur->name = strdup(setting))) {
virReportOOMError();
virConfFreeValue(value);
VIR_FREE(cur);
return (-1);
}
cur->value = value;
if (prev) {
cur->next = prev->next;
prev->next = cur;
} else {
cur->next = conf->entries;
conf->entries = cur;
}
} else {
virConfFreeValue(cur->value);
cur->value = value;
}
return (0);
}
/**
* virConfWriteFile:
* @filename: the path to the configuration file.
* @conf: the conf
*
* Writes a configuration file back to a file.
*
* Returns the number of bytes written or -1 in case of error.
*/
int
virConfWriteFile(const char *filename, virConfPtr conf)
{
virBuffer buf = VIR_BUFFER_INITIALIZER;
virConfEntryPtr cur;
int ret;
int fd;
char *content;
unsigned int use;
if (conf == NULL)
return(-1);
cur = conf->entries;
while (cur != NULL) {
virConfSaveEntry(&buf, cur);
cur = cur->next;
}
if (virBufferError(&buf)) {
virBufferFreeAndReset(&buf);
virReportOOMError();
return -1;
}
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR );
if (fd < 0) {
virBufferFreeAndReset(&buf);
virConfError(NULL, VIR_ERR_WRITE_FAILED, _("failed to open file"));
return -1;
}
use = virBufferUse(&buf);
content = virBufferContentAndReset(&buf);
ret = safewrite(fd, content, use);
VIR_FREE(content);
VIR_FORCE_CLOSE(fd);
if (ret != (int)use) {
virConfError(NULL, VIR_ERR_WRITE_FAILED, _("failed to save content"));
return -1;
}
return ret;
}
/**
* virConfWriteMem:
* @memory: pointer to the memory to store the config file
* @len: pointer to the length in bytes of the store, on output the size
* @conf: the conf
*
* Writes a configuration file back to a memory area. @len is an IN/OUT
* parameter, it indicates the size available in bytes, and on output the
* size required for the configuration file (even if the call fails due to
* insufficient space).
*
* Returns the number of bytes written or -1 in case of error.
*/
int
virConfWriteMem(char *memory, int *len, virConfPtr conf)
{
virBuffer buf = VIR_BUFFER_INITIALIZER;
virConfEntryPtr cur;
char *content;
unsigned int use;
if ((memory == NULL) || (len == NULL) || (*len <= 0) || (conf == NULL))
return(-1);
cur = conf->entries;
while (cur != NULL) {
virConfSaveEntry(&buf, cur);
cur = cur->next;
}
if (virBufferError(&buf)) {
virBufferFreeAndReset(&buf);
virReportOOMError();
return -1;
}
use = virBufferUse(&buf);
content = virBufferContentAndReset(&buf);
if ((int)use >= *len) {
*len = (int)use;
VIR_FREE(content);
return -1;
}
memcpy(memory, content, use);
VIR_FREE(content);
*len = use;
return use;
}