Golang free示例

说明

golang free示例是从最受好评的开源项目中提取的实现代码,你可以参考下面示例的使用方式。

编程语言: Golang

命名空间/包名称: C

示例#1
文件: osr.go 项目: sn-amber/gdal

// Set geographic coordinate system
func (sr SpatialReference) SetGeographicCS(
	geogName, datumName, spheroidName string,
	semiMajor, flattening float64,
	pmName string,
	offset float64,
	angularUnits string,
	toRadians float64,
) error {
	cGeogName := C.CString(geogName)
	defer C.free(unsafe.Pointer(cGeogName))
	cDatumName := C.CString(datumName)
	defer C.free(unsafe.Pointer(cDatumName))
	cSpheroidName := C.CString(spheroidName)
	defer C.free(unsafe.Pointer(cSpheroidName))
	cPMName := C.CString(pmName)
	defer C.free(unsafe.Pointer(cPMName))
	cAngularUnits := C.CString(angularUnits)
	defer C.free(unsafe.Pointer(cAngularUnits))
	return C.OSRSetGeogCS(
		sr.cval,
		cGeogName,
		cDatumName,
		cSpheroidName,
		C.double(semiMajor),
		C.double(flattening),
		cPMName,
		C.double(offset),
		cAngularUnits,
		C.double(toRadians),
	).Err()
}

示例#2
文件: pq.go 项目: dvarrazzo/pger

func connect(conninfo string) (*PgConn, error) {
	cs := C.CString(conninfo)
	defer C.free(unsafe.Pointer(cs))
	conn := C.PQconnectdb(cs)
	if C.PQstatus(conn) != C.CONNECTION_OK {
		cerr := C.PQerrorMessage(conn)
		err := fmt.Errorf("connection failed: %s", C.GoString(cerr))
		C.PQfinish(conn)
		return nil, err
	}

	// TODO: support other encodings?
	pname := C.CString("client_encoding")
	defer C.free(unsafe.Pointer(pname))
	cenc := C.PQparameterStatus(conn, pname)
	if cenc == nil {
		err := errors.New("connection failed: no client encoding")
		C.PQfinish(conn)
		return nil, err
	}
	if enc := C.GoString(cenc); enc != "UTF8" {
		err := fmt.Errorf(
			"connection failed: client encoding not supported: %s", enc)
		C.PQfinish(conn)
		return nil, err
	}

	// one-line error message
	C.PQsetErrorVerbosity(conn, C.PQERRORS_TERSE)

	return &PgConn{conn: conn, conninfo: conninfo}, nil
}

示例#3
文件: iconv.go 项目: pombredanne/goconv

func OpenWithFallback(fromCode string, toCode string, fallbackPolicy int) (ic *Iconv, err error) {
	var pIconv C.iconv_t

	toCodeCharPtr := C.CString(toCode)
	defer C.free(unsafe.Pointer(toCodeCharPtr))
	fromCodeCharPtr := C.CString(fromCode)
	defer C.free(unsafe.Pointer(fromCodeCharPtr))

	pIconv, err = C.iconv_open(toCodeCharPtr, fromCodeCharPtr)
	if err == nil {
		if pIconv == nil {
			err = NilIconvPointer
			return
		}
		if fallbackPolicy == DISCARD_UNRECOGNIZED {
			ic = &Iconv{pIconv: pIconv, fallbackPolicy: fallbackPolicy, fallback: fallbackDiscardUnrecognized}
		} else if fallbackPolicy == KEEP_UNRECOGNIZED {
			ic = &Iconv{pIconv: pIconv, fallbackPolicy: fallbackPolicy, fallback: fallbackKeepIntactUnrecognized}
		} else if fallbackPolicy == NEXT_ENC_UNRECOGNIZED {
			ic = &Iconv{pIconv: pIconv, fallbackPolicy: fallbackPolicy}
		} else {
			err = InvalidFallbackPolicy
		}
	}
	return
}

示例#4
文件: reference.go 项目: jingweno/git2go

func (v *Reference) Rename(name string, force bool, sig *Signature, msg string) (*Reference, error) {
	var ptr *C.git_reference
	cname := C.CString(name)
	defer C.free(unsafe.Pointer(cname))

	csig := sig.toC()
	defer C.free(unsafe.Pointer(csig))

	var cmsg *C.char
	if msg == "" {
		cmsg = nil
	} else {
		cmsg = C.CString(msg)
		defer C.free(unsafe.Pointer(cmsg))
	}

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	ret := C.git_reference_rename(&ptr, v.ptr, cname, cbool(force), csig, cmsg)

	if ret < 0 {
		return nil, MakeGitError(ret)
	}

	return newReferenceFromC(ptr), nil
}

示例#5
文件: dtrace.go 项目: chrisa/go-dtrace

func (provider *Provider) AddProbe(function string, name string, signature ...reflect.Kind) Probe {
	cFunction := C.CString(function)
	cName := C.CString(name)
	defer C.free(unsafe.Pointer(cFunction))
	defer C.free(unsafe.Pointer(cName))

	cTypes := make([]*C.char, len(signature))

	for i, kind := range signature {
		switch kind {
		case reflect.Int:
			cTypes[i] = C.CString("int")
			defer C.free(unsafe.Pointer(cTypes[i]))
		case reflect.String:
			cTypes[i] = C.CString("char *")
			defer C.free(unsafe.Pointer(cTypes[i]))
		default:
			cTypes[i] = nil
		}
	}

	probedef := C.usdt_create_probe(cFunction, cName, C.size_t(len(signature)), &cTypes[0])
	C.usdt_provider_add_probe(provider.provider_t, probedef)

	newProbe := Probe{
		function,
		name,
		probedef,
	}

	provider.Probes = append(provider.Probes, newProbe)

	return newProbe
}

示例#6
文件: low.go 项目: lye/go-db-sqlite3

func sqlOpen(name string, flags int, vfs string) (conn *sqlConnection, rc int) {
	conn = new(sqlConnection)

	p := C.CString(name)
	if len(vfs) > 0 {
		q := C.CString(vfs)
		rc = int(C.sqlite3_open_v2(p, &conn.handle, C.int(flags), q))
		C.free(unsafe.Pointer(q))
	} else {
		rc = int(C.sqlite3_open_v2(p, &conn.handle, C.int(flags), nil))
	}
	C.free(unsafe.Pointer(p))

	// We could get a handle even if there's an error, see
	// http://www.sqlite.org/c3ref/open.html for details.
	// Initially we didn't want to return a connection on
	// error, but we actually have to since we want to fill
	// in a SystemError struct. Sigh.
	//	if rc != StatusOk && conn.handle != nil {
	//		_ = conn.sqlClose();
	//		conn = nil;
	//	}

	return
}

示例#7
文件: db.go 项目: olehz/hyperleveldb-go

// GetApproximateSizes returns the approximate number of bytes of file system
// space used by one or more key ranges.
//
// The keys counted will begin at Range.Start and end on the key before
// Range.Limit.
func (db *DB) GetApproximateSizes(ranges []Range) []uint64 {
	starts := make([]*C.char, len(ranges))
	limits := make([]*C.char, len(ranges))
	startLens := make([]C.size_t, len(ranges))
	limitLens := make([]C.size_t, len(ranges))
	for i, r := range ranges {
		starts[i] = C.CString(string(r.Start))
		startLens[i] = C.size_t(len(r.Start))
		limits[i] = C.CString(string(r.Limit))
		limitLens[i] = C.size_t(len(r.Limit))
	}
	sizes := make([]uint64, len(ranges))
	numranges := C.int(len(ranges))
	startsPtr := &starts[0]
	limitsPtr := &limits[0]
	startLensPtr := &startLens[0]
	limitLensPtr := &limitLens[0]
	sizesPtr := (*C.uint64_t)(&sizes[0])
	C.hyperleveldb_rocksdb_approximate_sizes(
		db.Ldb, numranges, startsPtr, startLensPtr,
		limitsPtr, limitLensPtr, sizesPtr)
	for i := range ranges {
		C.free(unsafe.Pointer(starts[i]))
		C.free(unsafe.Pointer(limits[i]))
	}
	return sizes
}

示例#8
文件: configure.go 项目: getlantern/tunio

// ConfigureFD sets up the tun device using a file descriptor.
func ConfigureFD(tunFd int, tunMTU int, ipaddr, netmask, udpgw string, d dialer) error {
	if d == nil {
		d = dummyDialer
	}

	Dialer = d
	udpGwServerAddress = udpgw

	ctunFd := C.int(tunFd)
	ctunMTU := C.int(tunMTU)
	cipaddr := C.CString(ipaddr)
	cnetmask := C.CString(netmask)
	cudpgw_addr := C.CString(udpgw)

	defer func() {
		C.free(unsafe.Pointer(cipaddr))
		C.free(unsafe.Pointer(cnetmask))
		C.free(unsafe.Pointer(cudpgw_addr))
	}()

	log.Printf("Configuring with file descriptor...")

	if err_t := C.configure_fd(ctunFd, ctunMTU, cipaddr, cnetmask, cudpgw_addr); err_t != C.ERR_OK {
		return errors.New("Failed to configure device.")
	}

	return nil
}

示例#9
文件: configure.go 项目: getlantern/tunio

// ConfigureTUN sets up the tun device, this is equivalent to the
// badvpn-tun2socks configuration, except for the --socks-server-addr.
func ConfigureTUN(tundev, ipaddr, netmask, udpgw string, d dialer) error {
	if d == nil {
		d = dummyDialer
	}

	Dialer = d
	udpGwServerAddress = udpgw

	ctundev := C.CString(tundev)
	cipaddr := C.CString(ipaddr)
	cnetmask := C.CString(netmask)
	cudpgw_addr := C.CString(udpgw)

	defer func() {
		C.free(unsafe.Pointer(ctundev))
		C.free(unsafe.Pointer(cipaddr))
		C.free(unsafe.Pointer(cnetmask))
		C.free(unsafe.Pointer(cudpgw_addr))
	}()

	log.Printf("Configuring with TUN device...")

	if err_t := C.configure_tun(ctundev, cipaddr, cnetmask, cudpgw_addr); err_t != C.ERR_OK {
		return errors.New("Failed to configure device.")
	}

	return nil
}

示例#10
文件: util.go 项目: matomesc/rkt

// GetRunningSlice attempts to retrieve the name of the systemd slice in which
// the current process is running.
// This function is a wrapper around the libsystemd C library; if it cannot be
// opened, an error is returned.
func GetRunningSlice() (slice string, err error) {
	var h *libHandle
	h, err = getHandle()
	if err != nil {
		return
	}
	defer func() {
		if err1 := h.Close(); err1 != nil {
			err = err1
		}
	}()

	sym := C.CString("sd_pid_get_slice")
	defer C.free(unsafe.Pointer(sym))
	sd_pid_get_slice := C.dlsym(h.handle, sym)
	if sd_pid_get_slice == nil {
		err = fmt.Errorf("error resolving sd_pid_get_slice function")
		return
	}

	var s string
	sl := C.CString(s)
	defer C.free(unsafe.Pointer(sl))

	ret := C.my_sd_pid_get_slice(sd_pid_get_slice, 0, &sl)
	if ret < 0 {
		err = fmt.Errorf("error calling sd_pid_get_slice: %v", syscall.Errno(-ret))
		return
	}

	return C.GoString(sl), nil
}

示例#11
文件: util.go 项目: matomesc/rkt

// CurrentUnitName attempts to retrieve the name of the systemd system unit
// from which the calling process has been invoked. It wraps the systemd
// `sd_pid_get_unit` call, with the same caveat: for processes not part of a
// systemd system unit, this function will return an error.
func CurrentUnitName() (unit string, err error) {
	var h *libHandle
	h, err = getHandle()
	if err != nil {
		return
	}
	defer func() {
		if err1 := h.Close(); err1 != nil {
			err = err1
		}
	}()

	sym := C.CString("sd_pid_get_unit")
	defer C.free(unsafe.Pointer(sym))
	sd_pid_get_unit := C.dlsym(h.handle, sym)
	if sd_pid_get_unit == nil {
		err = fmt.Errorf("error resolving sd_pid_get_unit function")
		return
	}

	var s string
	u := C.CString(s)
	defer C.free(unsafe.Pointer(u))

	ret := C.my_sd_pid_get_unit(sd_pid_get_unit, 0, &u)
	if ret < 0 {
		err = fmt.Errorf("error calling sd_pid_get_unit: %v", syscall.Errno(-ret))
		return
	}

	unit = C.GoString(u)
	return
}

示例#12
文件: webview.go 项目: visionect/go-webkit2

// LoadHTML loads the given content string with the specified baseURI. The MIME
// type of the document will be "text/html".
//
// See also: webkit_web_view_load_html at
// http://webkitgtk.org/reference/webkit2gtk/stable/WebKitWebView.html#webkit-web-view-load-html
func (v *WebView) LoadHTML(content, baseURI string) {
	cContent := C.CString(content)
	defer C.free(unsafe.Pointer(cContent))
	cBaseURI := C.CString(baseURI)
	defer C.free(unsafe.Pointer(cBaseURI))
	C.webkit_web_view_load_html(v.webView, (*C.gchar)(cContent), (*C.gchar)(cBaseURI))
}

示例#13
文件: osr.go 项目: sn-amber/gdal

// Sets the authority for a node
func (sr SpatialReference) SetAuthority(target, authority string, code int) error {
	cTarget := C.CString(target)
	defer C.free(unsafe.Pointer(cTarget))
	cAuthority := C.CString(authority)
	defer C.free(unsafe.Pointer(cAuthority))
	return C.OSRSetAuthority(sr.cval, cTarget, cAuthority, C.int(code)).Err()
}

示例#14
文件: osr.go 项目: sn-amber/gdal

// Set up the vertical coordinate system
func (sr SpatialReference) SetVerticalCS(csName, datumName string, datumType int) error {
	cCSName := C.CString(csName)
	defer C.free(unsafe.Pointer(cCSName))
	cDatumName := C.CString(datumName)
	defer C.free(unsafe.Pointer(cDatumName))
	return C.OSRSetVertCS(sr.cval, cCSName, cDatumName, C.int(datumType)).Err()
}

示例#15
文件: ioctx.go 项目: mittalms/go-ceph

// function that lists all the xattrs for an object, since xattrs are
// a k-v pair, this function returns a map of k-v pairs on
// success, error code on failure
func (ioctx *IOContext) ListXattrs(oid string) (map[string][]byte, error) {
	c_oid := C.CString(oid)
	defer C.free(unsafe.Pointer(c_oid))

	var it C.rados_xattrs_iter_t

	ret := C.rados_getxattrs(ioctx.ioctx, c_oid, &it)
	if ret < 0 {
		return nil, GetRadosError(ret)
	}
	defer func() { C.rados_getxattrs_end(it) }()
	m := make(map[string][]byte)
	for {
		var c_name, c_val *C.char
		var c_len C.size_t
		defer C.free(unsafe.Pointer(c_name))
		defer C.free(unsafe.Pointer(c_val))

		ret := C.rados_getxattrs_next(it, &c_name, &c_val, &c_len)
		if ret < 0 {
			return nil, GetRadosError(ret)
		}
		// rados api returns a null name,val & 0-length upon
		// end of iteration
		if c_name == nil {
			return m, nil // stop iteration
		}
		m[C.GoString(c_name)] = C.GoBytes(unsafe.Pointer(c_val), (C.int)(c_len))
	}
}

示例#16
文件: beacon.go 项目: roger2000hk/goczmq

// Publish publishes an announcement at an interval
func (b *Beacon) Publish(announcement string, interval int) error {
	cmd := C.CString("PUBLISH")
	defer C.free(unsafe.Pointer(cmd))

	cAnnouncement := C.CString(announcement)
	defer C.free(unsafe.Pointer(cAnnouncement))

	cInterval := C.CString(strconv.Itoa(interval))
	defer C.free(unsafe.Pointer(cInterval))

	rc := C.zstr_sendm(unsafe.Pointer(b.zactorT), cmd)
	if rc == -1 {
		return ErrActorCmd
	}

	rc = C.zstr_sendm(unsafe.Pointer(b.zactorT), cAnnouncement)
	if rc == -1 {
		return ErrActorCmd
	}

	rc = C.zstr_send(unsafe.Pointer(b.zactorT), cInterval)
	if rc == -1 {
		return ErrActorCmd
	}

	return nil
}

示例#17
文件: ioctx.go 项目: mittalms/go-ceph

// Remove the specified `keys` from the omap `oid`
func (ioctx *IOContext) RmOmapKeys(oid string, keys []string) error {
	c_oid := C.CString(oid)
	defer C.free(unsafe.Pointer(c_oid))

	var c *C.char
	ptrSize := unsafe.Sizeof(c)

	c_keys := C.malloc(C.size_t(len(keys)) * C.size_t(ptrSize))
	defer C.free(unsafe.Pointer(c_keys))

	i := 0
	for _, key := range keys {
		c_key_ptr := (**C.char)(unsafe.Pointer(uintptr(c_keys) + uintptr(i)*ptrSize))
		*c_key_ptr = C.CString(key)
		defer C.free(unsafe.Pointer(*c_key_ptr))
		i++
	}

	op := C.rados_create_write_op()
	C.rados_write_op_omap_rm_keys(
		op,
		(**C.char)(c_keys),
		C.size_t(len(keys)))

	ret := C.rados_write_op_operate(op, ioctx.ioctx, c_oid, nil, 0)
	C.rados_release_write_op(op)

	return GetRadosError(ret)
}

示例#18
文件: cgo_double.go 项目: jvlmdr/linalg

// void dsyevd_(char *jobz, char *uplo, int *n, double *A, int *ldA, double *W,
//		double *work, int *lwork, int *iwork, int *liwork, int *info);
func dsyevd(jobz, uplo string, N int, A []float64, lda int, W []float64) int {
	var info int = 0
	var lwork int = -1
	var liwork int = -1
	var iwork int32
	var work float64

	cjobz := C.CString(jobz)
	defer C.free(unsafe.Pointer(cjobz))
	cuplo := C.CString(uplo)
	defer C.free(unsafe.Pointer(cuplo))

	// pre-calculate work buffer size
	C.dsyevd_(cjobz, cuplo, (*C.int)(unsafe.Pointer(&N)), nil,
		(*C.int)(unsafe.Pointer(&lda)), nil,
		(*C.double)(unsafe.Pointer(&work)), (*C.int)(unsafe.Pointer(&lwork)),
		(*C.int)(unsafe.Pointer(&iwork)), (*C.int)(unsafe.Pointer(&liwork)),
		(*C.int)(unsafe.Pointer(&info)))

	// allocate work area
	lwork = int(work)
	wbuf := make([]float64, lwork)
	liwork = int(iwork)
	wibuf := make([]int32, liwork)

	C.dsyevd_(cjobz, cuplo, (*C.int)(unsafe.Pointer(&N)),
		(*C.double)(unsafe.Pointer(&A[0])),
		(*C.int)(unsafe.Pointer(&lda)), (*C.double)(unsafe.Pointer(&W[0])),
		(*C.double)(unsafe.Pointer(&wbuf[0])), (*C.int)(unsafe.Pointer(&lwork)),
		(*C.int)(unsafe.Pointer(&wibuf[0])), (*C.int)(unsafe.Pointer(&liwork)),
		(*C.int)(unsafe.Pointer(&info)))
	return info
}

示例#19
文件: conn.go 项目: jeffycf/goci-1

func (conn *connection) performLogon(dsn string) error {

	user, pwd, host := parseDsn(dsn)
	puser := C.CString(user)
	defer C.free(unsafe.Pointer(puser))
	ppwd := C.CString(pwd)
	defer C.free(unsafe.Pointer(ppwd))
	phost := C.CString(host)
	defer C.free(unsafe.Pointer(phost))

	result := C.OCILogon2((*C.OCIEnv)(unsafe.Pointer(conn.env)),
		(*C.OCIError)(conn.err),
		(**C.OCIServer)(unsafe.Pointer(&conn.svr)),
		(*C.OraText)(unsafe.Pointer(puser)),
		C.ub4(C.strlen(puser)),
		(*C.OraText)(unsafe.Pointer(ppwd)),
		C.ub4(C.strlen(ppwd)),
		(*C.OraText)(unsafe.Pointer(phost)),
		C.ub4(C.strlen(phost)),
		C.OCI_LOGON2_STMTCACHE)
	if result != C.OCI_SUCCESS {
		return ociGetError(conn.err)
	}
	return nil
}

示例#20
文件: tdb.go 项目: traildb/traildb-go

func NewTrailDBConstructor(path string, ofields ...string) (*TrailDBConstructor, error) {
	cons := C.tdb_cons_init()
	cpath := C.CString(path)
	defer C.free(unsafe.Pointer(cpath))

	var ofield_p *C.char
	ptrSize := unsafe.Sizeof(ofield_p)

	// Allocate the char** list.
	ptr := C.malloc(C.size_t(len(ofields)) * C.size_t(ptrSize))
	defer C.free(ptr)

	// Assign each byte slice to its appropriate offset.
	for i := 0; i < len(ofields); i++ {
		element := (**C.char)(unsafe.Pointer(uintptr(ptr) + uintptr(i)*ptrSize))
		cofield := C.CString(ofields[i])
		defer C.free(unsafe.Pointer(cofield))
		*element = cofield
	}

	if err := C.tdb_cons_open(cons, cpath, (**C.char)(ptr), C.uint64_t(len(ofields))); err != 0 {
		return nil, errors.New(errToString(err))
	}
	return &TrailDBConstructor{
		cons:         cons,
		path:         path,
		ofields:      ofields,
		valueLengths: make([]C.uint64_t, len(ofields)),
		valuePtr:     C.malloc(C.size_t(len(ofields)) * C.size_t(ptrSize)),
	}, nil
}

示例#21
文件: reference.go 项目: jingweno/git2go

func (v *Reference) SetSymbolicTarget(target string, sig *Signature, msg string) (*Reference, error) {
	var ptr *C.git_reference

	ctarget := C.CString(target)
	defer C.free(unsafe.Pointer(ctarget))

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()

	csig := sig.toC()
	defer C.free(unsafe.Pointer(csig))

	var cmsg *C.char
	if msg == "" {
		cmsg = nil
	} else {
		cmsg = C.CString(msg)
		defer C.free(unsafe.Pointer(cmsg))
	}

	ret := C.git_reference_symbolic_set_target(&ptr, v.ptr, ctarget, csig, cmsg)
	if ret < 0 {
		return nil, MakeGitError(ret)
	}

	return newReferenceFromC(ptr), nil
}

示例#22
文件: vorbis.go 项目: grd/vorbis

func (p *Comment) AddTag(tag string, contents string) {
	cTag := C.CString(tag)
	cContents := C.CString(contents)
	C.vorbis_comment_add_tag((*C.vorbis_comment)(p), cTag, cContents)
	C.free(unsafe.Pointer(cTag))
	C.free(unsafe.Pointer(cContents))
}

示例#23
文件: instance.go 项目: egelmex/go-vlc

// VlmAddVOD adds a VOD with given input.
//
//     name: The name of the new broadcast.
//     input: The input MRL.
//     options: Additional options.
//     mux: The muxer of the vod media.
//     enabled: Enable the new broadcast?
//
func (this *Instance) VlmAddVOD(name, input, output, mux string, options []string, enabled bool) error {
	if this.ptr == nil {
		return os.EINVAL
	}

	a := C.CString(name)
	b := C.CString(input)
	c := C.int(len(options))
	d := make([]*C.char, len(options))

	for i := range d {
		d[i] = C.CString(options[i])
	}

	var e C.int
	if enabled {
		e = 1
	}

	f := C.CString(mux)

	C.libvlc_vlm_add_vod(this.ptr, a, b, c, *(***C.char)(unsafe.Pointer(&d)), e, f)

	C.free(unsafe.Pointer(a))
	C.free(unsafe.Pointer(b))

	for i := range d {
		C.free(unsafe.Pointer(d[i]))
	}

	C.free(unsafe.Pointer(f))
	return checkError()
}

示例#24
文件: ogr.go 项目: colek42/gdal

// Create a new layer on the data source
func (ds DataSource) CreateLayer(
	name string,
	sr SpatialReference,
	geomType GeometryType,
	options []string,
) Layer {
	cName := C.CString(name)
	defer C.free(unsafe.Pointer(cName))

	length := len(options)
	opts := make([]*C.char, length+1)
	for i := 0; i < length; i++ {
		opts[i] = C.CString(options[i])
		defer C.free(unsafe.Pointer(opts[i]))
	}
	opts[length] = (*C.char)(unsafe.Pointer(nil))

	layer := C.OGR_DS_CreateLayer(
		ds.cval,
		cName,
		sr.cval,
		C.OGRwkbGeometryType(geomType),
		(**C.char)(unsafe.Pointer(&opts[0])),
	)
	return Layer{layer}
}

示例#25
文件: magick.go 项目: mat/magick

// GetProperty() retreives the given attribute or freeform property
// string on the underlying Image
func (im *MagickImage) GetProperty(prop string) (value string) {
	c_prop := C.CString(prop)
	defer C.free(unsafe.Pointer(c_prop))
	c_value := C.GetImageProperty(im.Image, c_prop)
	defer C.free(unsafe.Pointer(c_value))
	return C.GoString(c_value)
}

示例#26
文件: glib.go 项目: vvanpo/gotk3

// Emit is a wrapper around g_signal_emitv() and emits the signal
// specified by the string s to an Object.  Arguments to callback
// functions connected to this signal must be specified in args.  Emit()
// returns an interface{} which must be type asserted as the Go
// equivalent type to the return value for native C callback.
//
// Note that this code is unsafe in that the types of values in args are
// not checked against whether they are suitable for the callback.
func (v *Object) Emit(s string, args ...interface{}) (interface{}, error) {
	cstr := C.CString(s)
	defer C.free(unsafe.Pointer(cstr))

	// Create array of this instance and arguments
	valv := C.alloc_gvalue_list(C.int(len(args)) + 1)
	defer C.free(unsafe.Pointer(valv))

	// Add args and valv
	val, err := GValue(v)
	if err != nil {
		return nil, errors.New("Error converting Object to GValue: " + err.Error())
	}
	C.val_list_insert(valv, C.int(0), val.native())
	for i := range args {
		val, err := GValue(args[i])
		if err != nil {
			return nil, fmt.Errorf("Error converting arg %d to GValue: %s", i, err.Error())
		}
		C.val_list_insert(valv, C.int(i+1), val.native())
	}

	t := v.TypeFromInstance()
	// TODO: use just the signal name
	id := C.g_signal_lookup((*C.gchar)(cstr), C.GType(t))

	ret, err := ValueAlloc()
	if err != nil {
		return nil, errors.New("Error creating Value for return value")
	}
	C.g_signal_emitv(valv, id, C.GQuark(0), ret.native())

	return ret.GoValue()
}

示例#27
文件: pgdriver.go 项目: NDrive/gopgsqldriver

func (c *driverConn) Prepare(query string) (driver.Stmt, error) {
	// Generate unique statement name.
	stmtname := strconv.Itoa(c.stmtNum)
	cstmtname := C.CString(stmtname)
	c.stmtNum++
	defer C.free(unsafe.Pointer(cstmtname))
	stmtstr := C.CString(query)
	defer C.free(unsafe.Pointer(stmtstr))
	res := C.PQprepare(c.db, cstmtname, stmtstr, 0, nil)
	err := resultError(res)
	if err != nil {
		C.PQclear(res)
		return nil, err
	}
	stmtinfo := C.PQdescribePrepared(c.db, cstmtname)
	err = resultError(stmtinfo)
	if err != nil {
		C.PQclear(stmtinfo)
		return nil, err
	}
	defer C.PQclear(stmtinfo)
	nparams := int(C.PQnparams(stmtinfo))
	statement := &driverStmt{stmtname, c.db, res, nparams}
	runtime.SetFinalizer(statement, (*driverStmt).Close)
	return statement, nil
}

示例#28
文件: clone.go 项目: jezell/git2go

func Clone(url string, path string, options *CloneOptions) (*Repository, error) {
	repo := new(Repository)

	curl := C.CString(url)
	defer C.free(unsafe.Pointer(curl))

	cpath := C.CString(path)
	defer C.free(unsafe.Pointer(cpath))

	var copts C.git_clone_options
	populateCloneOptions(&copts, options)
	defer freeCheckoutOpts(&copts.checkout_opts)

	if len(options.CheckoutBranch) != 0 {
		copts.checkout_branch = C.CString(options.CheckoutBranch)
		defer C.free(unsafe.Pointer(copts.checkout_branch))
	}

	runtime.LockOSThread()
	defer runtime.UnlockOSThread()
	ret := C.git_clone(&repo.ptr, curl, cpath, &copts)
	if ret < 0 {
		return nil, MakeGitError(ret)
	}

	runtime.SetFinalizer(repo, (*Repository).Free)
	return repo, nil
}

示例#29
文件: avahi.go 项目: kleopatra999/cups-connector

func (z *zeroconf) removePrinter(name string) error {
	z.spMutex.Lock()
	defer z.spMutex.Unlock()

	r, exists := z.printers[name]
	if !exists {
		return fmt.Errorf("printer %s cannot be updated for Avahi publishing; it was never added", name)
	}

	if z.state == C.AVAHI_CLIENT_S_RUNNING && r.group != nil {
		C.avahi_threaded_poll_lock(z.threadedPoll)
		defer C.avahi_threaded_poll_unlock(z.threadedPoll)

		var errstr *C.char
		C.removeAvahiGroup(z.threadedPoll, r.group, &errstr)
		if errstr != nil {
			err := errors.New(C.GoString(errstr))
			C.free(unsafe.Pointer(errstr))
			return err
		}
	}

	C.free(unsafe.Pointer(r.name))

	delete(z.printers, name)
	return nil
}

示例#30
文件: osr.go 项目: sn-amber/gdal

// Set the linear units for the target node
func (sr SpatialReference) SetTargetLinearUnits(target, units string, toMeters float64) error {
	cTarget := C.CString(target)
	defer C.free(unsafe.Pointer(cTarget))
	cUnits := C.CString(units)
	defer C.free(unsafe.Pointer(cUnits))
	return C.OSRSetTargetLinearUnits(sr.cval, cTarget, cUnits, C.double(toMeters)).Err()
}

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