879 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			879 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // Copyright 2013 Julien Schmidt. All rights reserved.
 | |
| // Use of this source code is governed by a BSD-style license that can be found
 | |
| // at https://github.com/julienschmidt/httprouter/blob/master/LICENSE
 | |
| 
 | |
| package gin
 | |
| 
 | |
| import (
 | |
| 	"bytes"
 | |
| 	"net/url"
 | |
| 	"strings"
 | |
| 	"unicode"
 | |
| 	"unicode/utf8"
 | |
| 
 | |
| 	"github.com/gin-gonic/gin/internal/bytesconv"
 | |
| )
 | |
| 
 | |
| var (
 | |
| 	strColon = []byte(":")
 | |
| 	strStar  = []byte("*")
 | |
| 	strSlash = []byte("/")
 | |
| )
 | |
| 
 | |
| // Param is a single URL parameter, consisting of a key and a value.
 | |
| type Param struct {
 | |
| 	Key   string
 | |
| 	Value string
 | |
| }
 | |
| 
 | |
| // Params is a Param-slice, as returned by the router.
 | |
| // The slice is ordered, the first URL parameter is also the first slice value.
 | |
| // It is therefore safe to read values by the index.
 | |
| type Params []Param
 | |
| 
 | |
| // Get returns the value of the first Param which key matches the given name and a boolean true.
 | |
| // If no matching Param is found, an empty string is returned and a boolean false .
 | |
| func (ps Params) Get(name string) (string, bool) {
 | |
| 	for _, entry := range ps {
 | |
| 		if entry.Key == name {
 | |
| 			return entry.Value, true
 | |
| 		}
 | |
| 	}
 | |
| 	return "", false
 | |
| }
 | |
| 
 | |
| // ByName returns the value of the first Param which key matches the given name.
 | |
| // If no matching Param is found, an empty string is returned.
 | |
| func (ps Params) ByName(name string) (va string) {
 | |
| 	va, _ = ps.Get(name)
 | |
| 	return
 | |
| }
 | |
| 
 | |
| type methodTree struct {
 | |
| 	method string
 | |
| 	root   *node
 | |
| }
 | |
| 
 | |
| type methodTrees []methodTree
 | |
| 
 | |
| func (trees methodTrees) get(method string) *node {
 | |
| 	for _, tree := range trees {
 | |
| 		if tree.method == method {
 | |
| 			return tree.root
 | |
| 		}
 | |
| 	}
 | |
| 	return nil
 | |
| }
 | |
| 
 | |
| func min(a, b int) int {
 | |
| 	if a <= b {
 | |
| 		return a
 | |
| 	}
 | |
| 	return b
 | |
| }
 | |
| 
 | |
| func longestCommonPrefix(a, b string) int {
 | |
| 	i := 0
 | |
| 	max := min(len(a), len(b))
 | |
| 	for i < max && a[i] == b[i] {
 | |
| 		i++
 | |
| 	}
 | |
| 	return i
 | |
| }
 | |
| 
 | |
| // addChild will add a child node, keeping wildcardChild at the end
 | |
| func (n *node) addChild(child *node) {
 | |
| 	if n.wildChild && len(n.children) > 0 {
 | |
| 		wildcardChild := n.children[len(n.children)-1]
 | |
| 		n.children = append(n.children[:len(n.children)-1], child, wildcardChild)
 | |
| 	} else {
 | |
| 		n.children = append(n.children, child)
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func countParams(path string) uint16 {
 | |
| 	var n uint16
 | |
| 	s := bytesconv.StringToBytes(path)
 | |
| 	n += uint16(bytes.Count(s, strColon))
 | |
| 	n += uint16(bytes.Count(s, strStar))
 | |
| 	return n
 | |
| }
 | |
| 
 | |
| func countSections(path string) uint16 {
 | |
| 	s := bytesconv.StringToBytes(path)
 | |
| 	return uint16(bytes.Count(s, strSlash))
 | |
| }
 | |
| 
 | |
| type nodeType uint8
 | |
| 
 | |
| const (
 | |
| 	static nodeType = iota
 | |
| 	root
 | |
| 	param
 | |
| 	catchAll
 | |
| )
 | |
| 
 | |
| type node struct {
 | |
| 	path      string
 | |
| 	indices   string
 | |
| 	wildChild bool
 | |
| 	nType     nodeType
 | |
| 	priority  uint32
 | |
| 	children  []*node // child nodes, at most 1 :param style node at the end of the array
 | |
| 	handlers  HandlersChain
 | |
| 	fullPath  string
 | |
| }
 | |
| 
 | |
| // Increments priority of the given child and reorders if necessary
 | |
| func (n *node) incrementChildPrio(pos int) int {
 | |
| 	cs := n.children
 | |
| 	cs[pos].priority++
 | |
| 	prio := cs[pos].priority
 | |
| 
 | |
| 	// Adjust position (move to front)
 | |
| 	newPos := pos
 | |
| 	for ; newPos > 0 && cs[newPos-1].priority < prio; newPos-- {
 | |
| 		// Swap node positions
 | |
| 		cs[newPos-1], cs[newPos] = cs[newPos], cs[newPos-1]
 | |
| 	}
 | |
| 
 | |
| 	// Build new index char string
 | |
| 	if newPos != pos {
 | |
| 		n.indices = n.indices[:newPos] + // Unchanged prefix, might be empty
 | |
| 			n.indices[pos:pos+1] + // The index char we move
 | |
| 			n.indices[newPos:pos] + n.indices[pos+1:] // Rest without char at 'pos'
 | |
| 	}
 | |
| 
 | |
| 	return newPos
 | |
| }
 | |
| 
 | |
| // addRoute adds a node with the given handle to the path.
 | |
| // Not concurrency-safe!
 | |
| func (n *node) addRoute(path string, handlers HandlersChain) {
 | |
| 	fullPath := path
 | |
| 	n.priority++
 | |
| 
 | |
| 	// Empty tree
 | |
| 	if len(n.path) == 0 && len(n.children) == 0 {
 | |
| 		n.insertChild(path, fullPath, handlers)
 | |
| 		n.nType = root
 | |
| 		return
 | |
| 	}
 | |
| 
 | |
| 	parentFullPathIndex := 0
 | |
| 
 | |
| walk:
 | |
| 	for {
 | |
| 		// Find the longest common prefix.
 | |
| 		// This also implies that the common prefix contains no ':' or '*'
 | |
| 		// since the existing key can't contain those chars.
 | |
| 		i := longestCommonPrefix(path, n.path)
 | |
| 
 | |
| 		// Split edge
 | |
| 		if i < len(n.path) {
 | |
| 			child := node{
 | |
| 				path:      n.path[i:],
 | |
| 				wildChild: n.wildChild,
 | |
| 				nType:     static,
 | |
| 				indices:   n.indices,
 | |
| 				children:  n.children,
 | |
| 				handlers:  n.handlers,
 | |
| 				priority:  n.priority - 1,
 | |
| 				fullPath:  n.fullPath,
 | |
| 			}
 | |
| 
 | |
| 			n.children = []*node{&child}
 | |
| 			// []byte for proper unicode char conversion, see #65
 | |
| 			n.indices = bytesconv.BytesToString([]byte{n.path[i]})
 | |
| 			n.path = path[:i]
 | |
| 			n.handlers = nil
 | |
| 			n.wildChild = false
 | |
| 			n.fullPath = fullPath[:parentFullPathIndex+i]
 | |
| 		}
 | |
| 
 | |
| 		// Make new node a child of this node
 | |
| 		if i < len(path) {
 | |
| 			path = path[i:]
 | |
| 			c := path[0]
 | |
| 
 | |
| 			// '/' after param
 | |
| 			if n.nType == param && c == '/' && len(n.children) == 1 {
 | |
| 				parentFullPathIndex += len(n.path)
 | |
| 				n = n.children[0]
 | |
| 				n.priority++
 | |
| 				continue walk
 | |
| 			}
 | |
| 
 | |
| 			// Check if a child with the next path byte exists
 | |
| 			for i, max := 0, len(n.indices); i < max; i++ {
 | |
| 				if c == n.indices[i] {
 | |
| 					parentFullPathIndex += len(n.path)
 | |
| 					i = n.incrementChildPrio(i)
 | |
| 					n = n.children[i]
 | |
| 					continue walk
 | |
| 				}
 | |
| 			}
 | |
| 
 | |
| 			// Otherwise insert it
 | |
| 			if c != ':' && c != '*' && n.nType != catchAll {
 | |
| 				// []byte for proper unicode char conversion, see #65
 | |
| 				n.indices += bytesconv.BytesToString([]byte{c})
 | |
| 				child := &node{
 | |
| 					fullPath: fullPath,
 | |
| 				}
 | |
| 				n.addChild(child)
 | |
| 				n.incrementChildPrio(len(n.indices) - 1)
 | |
| 				n = child
 | |
| 			} else if n.wildChild {
 | |
| 				// inserting a wildcard node, need to check if it conflicts with the existing wildcard
 | |
| 				n = n.children[len(n.children)-1]
 | |
| 				n.priority++
 | |
| 
 | |
| 				// Check if the wildcard matches
 | |
| 				if len(path) >= len(n.path) && n.path == path[:len(n.path)] &&
 | |
| 					// Adding a child to a catchAll is not possible
 | |
| 					n.nType != catchAll &&
 | |
| 					// Check for longer wildcard, e.g. :name and :names
 | |
| 					(len(n.path) >= len(path) || path[len(n.path)] == '/') {
 | |
| 					continue walk
 | |
| 				}
 | |
| 
 | |
| 				// Wildcard conflict
 | |
| 				pathSeg := path
 | |
| 				if n.nType != catchAll {
 | |
| 					pathSeg = strings.SplitN(pathSeg, "/", 2)[0]
 | |
| 				}
 | |
| 				prefix := fullPath[:strings.Index(fullPath, pathSeg)] + n.path
 | |
| 				panic("'" + pathSeg +
 | |
| 					"' in new path '" + fullPath +
 | |
| 					"' conflicts with existing wildcard '" + n.path +
 | |
| 					"' in existing prefix '" + prefix +
 | |
| 					"'")
 | |
| 			}
 | |
| 
 | |
| 			n.insertChild(path, fullPath, handlers)
 | |
| 			return
 | |
| 		}
 | |
| 
 | |
| 		// Otherwise add handle to current node
 | |
| 		if n.handlers != nil {
 | |
| 			panic("handlers are already registered for path '" + fullPath + "'")
 | |
| 		}
 | |
| 		n.handlers = handlers
 | |
| 		n.fullPath = fullPath
 | |
| 		return
 | |
| 	}
 | |
| }
 | |
| 
 | |
| // Search for a wildcard segment and check the name for invalid characters.
 | |
| // Returns -1 as index, if no wildcard was found.
 | |
| func findWildcard(path string) (wildcard string, i int, valid bool) {
 | |
| 	// Find start
 | |
| 	for start, c := range []byte(path) {
 | |
| 		// A wildcard starts with ':' (param) or '*' (catch-all)
 | |
| 		if c != ':' && c != '*' {
 | |
| 			continue
 | |
| 		}
 | |
| 
 | |
| 		// Find end and check for invalid characters
 | |
| 		valid = true
 | |
| 		for end, c := range []byte(path[start+1:]) {
 | |
| 			switch c {
 | |
| 			case '/':
 | |
| 				return path[start : start+1+end], start, valid
 | |
| 			case ':', '*':
 | |
| 				valid = false
 | |
| 			}
 | |
| 		}
 | |
| 		return path[start:], start, valid
 | |
| 	}
 | |
| 	return "", -1, false
 | |
| }
 | |
| 
 | |
| func (n *node) insertChild(path string, fullPath string, handlers HandlersChain) {
 | |
| 	for {
 | |
| 		// Find prefix until first wildcard
 | |
| 		wildcard, i, valid := findWildcard(path)
 | |
| 		if i < 0 { // No wildcard found
 | |
| 			break
 | |
| 		}
 | |
| 
 | |
| 		// The wildcard name must only contain one ':' or '*' character
 | |
| 		if !valid {
 | |
| 			panic("only one wildcard per path segment is allowed, has: '" +
 | |
| 				wildcard + "' in path '" + fullPath + "'")
 | |
| 		}
 | |
| 
 | |
| 		// check if the wildcard has a name
 | |
| 		if len(wildcard) < 2 {
 | |
| 			panic("wildcards must be named with a non-empty name in path '" + fullPath + "'")
 | |
| 		}
 | |
| 
 | |
| 		if wildcard[0] == ':' { // param
 | |
| 			if i > 0 {
 | |
| 				// Insert prefix before the current wildcard
 | |
| 				n.path = path[:i]
 | |
| 				path = path[i:]
 | |
| 			}
 | |
| 
 | |
| 			child := &node{
 | |
| 				nType:    param,
 | |
| 				path:     wildcard,
 | |
| 				fullPath: fullPath,
 | |
| 			}
 | |
| 			n.addChild(child)
 | |
| 			n.wildChild = true
 | |
| 			n = child
 | |
| 			n.priority++
 | |
| 
 | |
| 			// if the path doesn't end with the wildcard, then there
 | |
| 			// will be another subpath starting with '/'
 | |
| 			if len(wildcard) < len(path) {
 | |
| 				path = path[len(wildcard):]
 | |
| 
 | |
| 				child := &node{
 | |
| 					priority: 1,
 | |
| 					fullPath: fullPath,
 | |
| 				}
 | |
| 				n.addChild(child)
 | |
| 				n = child
 | |
| 				continue
 | |
| 			}
 | |
| 
 | |
| 			// Otherwise we're done. Insert the handle in the new leaf
 | |
| 			n.handlers = handlers
 | |
| 			return
 | |
| 		}
 | |
| 
 | |
| 		// catchAll
 | |
| 		if i+len(wildcard) != len(path) {
 | |
| 			panic("catch-all routes are only allowed at the end of the path in path '" + fullPath + "'")
 | |
| 		}
 | |
| 
 | |
| 		if len(n.path) > 0 && n.path[len(n.path)-1] == '/' {
 | |
| 			pathSeg := strings.SplitN(n.children[0].path, "/", 2)[0]
 | |
| 			panic("catch-all wildcard '" + path +
 | |
| 				"' in new path '" + fullPath +
 | |
| 				"' conflicts with existing path segment '" + pathSeg +
 | |
| 				"' in existing prefix '" + n.path + pathSeg +
 | |
| 				"'")
 | |
| 		}
 | |
| 
 | |
| 		// currently fixed width 1 for '/'
 | |
| 		i--
 | |
| 		if path[i] != '/' {
 | |
| 			panic("no / before catch-all in path '" + fullPath + "'")
 | |
| 		}
 | |
| 
 | |
| 		n.path = path[:i]
 | |
| 
 | |
| 		// First node: catchAll node with empty path
 | |
| 		child := &node{
 | |
| 			wildChild: true,
 | |
| 			nType:     catchAll,
 | |
| 			fullPath:  fullPath,
 | |
| 		}
 | |
| 
 | |
| 		n.addChild(child)
 | |
| 		n.indices = string('/')
 | |
| 		n = child
 | |
| 		n.priority++
 | |
| 
 | |
| 		// second node: node holding the variable
 | |
| 		child = &node{
 | |
| 			path:     path[i:],
 | |
| 			nType:    catchAll,
 | |
| 			handlers: handlers,
 | |
| 			priority: 1,
 | |
| 			fullPath: fullPath,
 | |
| 		}
 | |
| 		n.children = []*node{child}
 | |
| 
 | |
| 		return
 | |
| 	}
 | |
| 
 | |
| 	// If no wildcard was found, simply insert the path and handle
 | |
| 	n.path = path
 | |
| 	n.handlers = handlers
 | |
| 	n.fullPath = fullPath
 | |
| }
 | |
| 
 | |
| // nodeValue holds return values of (*Node).getValue method
 | |
| type nodeValue struct {
 | |
| 	handlers HandlersChain
 | |
| 	params   *Params
 | |
| 	tsr      bool
 | |
| 	fullPath string
 | |
| }
 | |
| 
 | |
| type skippedNode struct {
 | |
| 	path        string
 | |
| 	node        *node
 | |
| 	paramsCount int16
 | |
| }
 | |
| 
 | |
| // Returns the handle registered with the given path (key). The values of
 | |
| // wildcards are saved to a map.
 | |
| // If no handle can be found, a TSR (trailing slash redirect) recommendation is
 | |
| // made if a handle exists with an extra (without the) trailing slash for the
 | |
| // given path.
 | |
| func (n *node) getValue(path string, params *Params, skippedNodes *[]skippedNode, unescape bool) (value nodeValue) {
 | |
| 	var globalParamsCount int16
 | |
| 
 | |
| walk: // Outer loop for walking the tree
 | |
| 	for {
 | |
| 		prefix := n.path
 | |
| 		if len(path) > len(prefix) {
 | |
| 			if path[:len(prefix)] == prefix {
 | |
| 				path = path[len(prefix):]
 | |
| 
 | |
| 				// Try all the non-wildcard children first by matching the indices
 | |
| 				idxc := path[0]
 | |
| 				for i, c := range []byte(n.indices) {
 | |
| 					if c == idxc {
 | |
| 						//  strings.HasPrefix(n.children[len(n.children)-1].path, ":") == n.wildChild
 | |
| 						if n.wildChild {
 | |
| 							index := len(*skippedNodes)
 | |
| 							*skippedNodes = (*skippedNodes)[:index+1]
 | |
| 							(*skippedNodes)[index] = skippedNode{
 | |
| 								path: prefix + path,
 | |
| 								node: &node{
 | |
| 									path:      n.path,
 | |
| 									wildChild: n.wildChild,
 | |
| 									nType:     n.nType,
 | |
| 									priority:  n.priority,
 | |
| 									children:  n.children,
 | |
| 									handlers:  n.handlers,
 | |
| 									fullPath:  n.fullPath,
 | |
| 								},
 | |
| 								paramsCount: globalParamsCount,
 | |
| 							}
 | |
| 						}
 | |
| 
 | |
| 						n = n.children[i]
 | |
| 						continue walk
 | |
| 					}
 | |
| 				}
 | |
| 
 | |
| 				if !n.wildChild {
 | |
| 					// If the path at the end of the loop is not equal to '/' and the current node has no child nodes
 | |
| 					// the current node needs to roll back to last valid skippedNode
 | |
| 					if path != "/" {
 | |
| 						for length := len(*skippedNodes); length > 0; length-- {
 | |
| 							skippedNode := (*skippedNodes)[length-1]
 | |
| 							*skippedNodes = (*skippedNodes)[:length-1]
 | |
| 							if strings.HasSuffix(skippedNode.path, path) {
 | |
| 								path = skippedNode.path
 | |
| 								n = skippedNode.node
 | |
| 								if value.params != nil {
 | |
| 									*value.params = (*value.params)[:skippedNode.paramsCount]
 | |
| 								}
 | |
| 								globalParamsCount = skippedNode.paramsCount
 | |
| 								continue walk
 | |
| 							}
 | |
| 						}
 | |
| 					}
 | |
| 
 | |
| 					// Nothing found.
 | |
| 					// We can recommend to redirect to the same URL without a
 | |
| 					// trailing slash if a leaf exists for that path.
 | |
| 					value.tsr = path == "/" && n.handlers != nil
 | |
| 					return
 | |
| 				}
 | |
| 
 | |
| 				// Handle wildcard child, which is always at the end of the array
 | |
| 				n = n.children[len(n.children)-1]
 | |
| 				globalParamsCount++
 | |
| 
 | |
| 				switch n.nType {
 | |
| 				case param:
 | |
| 					// fix truncate the parameter
 | |
| 					// tree_test.go  line: 204
 | |
| 
 | |
| 					// Find param end (either '/' or path end)
 | |
| 					end := 0
 | |
| 					for end < len(path) && path[end] != '/' {
 | |
| 						end++
 | |
| 					}
 | |
| 
 | |
| 					// Save param value
 | |
| 					if params != nil && cap(*params) > 0 {
 | |
| 						if value.params == nil {
 | |
| 							value.params = params
 | |
| 						}
 | |
| 						// Expand slice within preallocated capacity
 | |
| 						i := len(*value.params)
 | |
| 						*value.params = (*value.params)[:i+1]
 | |
| 						val := path[:end]
 | |
| 						if unescape {
 | |
| 							if v, err := url.QueryUnescape(val); err == nil {
 | |
| 								val = v
 | |
| 							}
 | |
| 						}
 | |
| 						(*value.params)[i] = Param{
 | |
| 							Key:   n.path[1:],
 | |
| 							Value: val,
 | |
| 						}
 | |
| 					}
 | |
| 
 | |
| 					// we need to go deeper!
 | |
| 					if end < len(path) {
 | |
| 						if len(n.children) > 0 {
 | |
| 							path = path[end:]
 | |
| 							n = n.children[0]
 | |
| 							continue walk
 | |
| 						}
 | |
| 
 | |
| 						// ... but we can't
 | |
| 						value.tsr = len(path) == end+1
 | |
| 						return
 | |
| 					}
 | |
| 
 | |
| 					if value.handlers = n.handlers; value.handlers != nil {
 | |
| 						value.fullPath = n.fullPath
 | |
| 						return
 | |
| 					}
 | |
| 					if len(n.children) == 1 {
 | |
| 						// No handle found. Check if a handle for this path + a
 | |
| 						// trailing slash exists for TSR recommendation
 | |
| 						n = n.children[0]
 | |
| 						value.tsr = (n.path == "/" && n.handlers != nil) || (n.path == "" && n.indices == "/")
 | |
| 					}
 | |
| 					return
 | |
| 
 | |
| 				case catchAll:
 | |
| 					// Save param value
 | |
| 					if params != nil {
 | |
| 						if value.params == nil {
 | |
| 							value.params = params
 | |
| 						}
 | |
| 						// Expand slice within preallocated capacity
 | |
| 						i := len(*value.params)
 | |
| 						*value.params = (*value.params)[:i+1]
 | |
| 						val := path
 | |
| 						if unescape {
 | |
| 							if v, err := url.QueryUnescape(path); err == nil {
 | |
| 								val = v
 | |
| 							}
 | |
| 						}
 | |
| 						(*value.params)[i] = Param{
 | |
| 							Key:   n.path[2:],
 | |
| 							Value: val,
 | |
| 						}
 | |
| 					}
 | |
| 
 | |
| 					value.handlers = n.handlers
 | |
| 					value.fullPath = n.fullPath
 | |
| 					return
 | |
| 
 | |
| 				default:
 | |
| 					panic("invalid node type")
 | |
| 				}
 | |
| 			}
 | |
| 		}
 | |
| 
 | |
| 		if path == prefix {
 | |
| 			// If the current path does not equal '/' and the node does not have a registered handle and the most recently matched node has a child node
 | |
| 			// the current node needs to roll back to last valid skippedNode
 | |
| 			if n.handlers == nil && path != "/" {
 | |
| 				for length := len(*skippedNodes); length > 0; length-- {
 | |
| 					skippedNode := (*skippedNodes)[length-1]
 | |
| 					*skippedNodes = (*skippedNodes)[:length-1]
 | |
| 					if strings.HasSuffix(skippedNode.path, path) {
 | |
| 						path = skippedNode.path
 | |
| 						n = skippedNode.node
 | |
| 						if value.params != nil {
 | |
| 							*value.params = (*value.params)[:skippedNode.paramsCount]
 | |
| 						}
 | |
| 						globalParamsCount = skippedNode.paramsCount
 | |
| 						continue walk
 | |
| 					}
 | |
| 				}
 | |
| 				//	n = latestNode.children[len(latestNode.children)-1]
 | |
| 			}
 | |
| 			// We should have reached the node containing the handle.
 | |
| 			// Check if this node has a handle registered.
 | |
| 			if value.handlers = n.handlers; value.handlers != nil {
 | |
| 				value.fullPath = n.fullPath
 | |
| 				return
 | |
| 			}
 | |
| 
 | |
| 			// If there is no handle for this route, but this route has a
 | |
| 			// wildcard child, there must be a handle for this path with an
 | |
| 			// additional trailing slash
 | |
| 			if path == "/" && n.wildChild && n.nType != root {
 | |
| 				value.tsr = true
 | |
| 				return
 | |
| 			}
 | |
| 
 | |
| 			if path == "/" && n.nType == static {
 | |
| 				value.tsr = true
 | |
| 				return
 | |
| 			}
 | |
| 
 | |
| 			// No handle found. Check if a handle for this path + a
 | |
| 			// trailing slash exists for trailing slash recommendation
 | |
| 			for i, c := range []byte(n.indices) {
 | |
| 				if c == '/' {
 | |
| 					n = n.children[i]
 | |
| 					value.tsr = (len(n.path) == 1 && n.handlers != nil) ||
 | |
| 						(n.nType == catchAll && n.children[0].handlers != nil)
 | |
| 					return
 | |
| 				}
 | |
| 			}
 | |
| 
 | |
| 			return
 | |
| 		}
 | |
| 
 | |
| 		// Nothing found. We can recommend to redirect to the same URL with an
 | |
| 		// extra trailing slash if a leaf exists for that path
 | |
| 		value.tsr = path == "/" ||
 | |
| 			(len(prefix) == len(path)+1 && prefix[len(path)] == '/' &&
 | |
| 				path == prefix[:len(prefix)-1] && n.handlers != nil)
 | |
| 
 | |
| 		// roll back to last valid skippedNode
 | |
| 		if !value.tsr && path != "/" {
 | |
| 			for length := len(*skippedNodes); length > 0; length-- {
 | |
| 				skippedNode := (*skippedNodes)[length-1]
 | |
| 				*skippedNodes = (*skippedNodes)[:length-1]
 | |
| 				if strings.HasSuffix(skippedNode.path, path) {
 | |
| 					path = skippedNode.path
 | |
| 					n = skippedNode.node
 | |
| 					if value.params != nil {
 | |
| 						*value.params = (*value.params)[:skippedNode.paramsCount]
 | |
| 					}
 | |
| 					globalParamsCount = skippedNode.paramsCount
 | |
| 					continue walk
 | |
| 				}
 | |
| 			}
 | |
| 		}
 | |
| 
 | |
| 		return
 | |
| 	}
 | |
| }
 | |
| 
 | |
| // Makes a case-insensitive lookup of the given path and tries to find a handler.
 | |
| // It can optionally also fix trailing slashes.
 | |
| // It returns the case-corrected path and a bool indicating whether the lookup
 | |
| // was successful.
 | |
| func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) ([]byte, bool) {
 | |
| 	const stackBufSize = 128
 | |
| 
 | |
| 	// Use a static sized buffer on the stack in the common case.
 | |
| 	// If the path is too long, allocate a buffer on the heap instead.
 | |
| 	buf := make([]byte, 0, stackBufSize)
 | |
| 	if length := len(path) + 1; length > stackBufSize {
 | |
| 		buf = make([]byte, 0, length)
 | |
| 	}
 | |
| 
 | |
| 	ciPath := n.findCaseInsensitivePathRec(
 | |
| 		path,
 | |
| 		buf,       // Preallocate enough memory for new path
 | |
| 		[4]byte{}, // Empty rune buffer
 | |
| 		fixTrailingSlash,
 | |
| 	)
 | |
| 
 | |
| 	return ciPath, ciPath != nil
 | |
| }
 | |
| 
 | |
| // Shift bytes in array by n bytes left
 | |
| func shiftNRuneBytes(rb [4]byte, n int) [4]byte {
 | |
| 	switch n {
 | |
| 	case 0:
 | |
| 		return rb
 | |
| 	case 1:
 | |
| 		return [4]byte{rb[1], rb[2], rb[3], 0}
 | |
| 	case 2:
 | |
| 		return [4]byte{rb[2], rb[3]}
 | |
| 	case 3:
 | |
| 		return [4]byte{rb[3]}
 | |
| 	default:
 | |
| 		return [4]byte{}
 | |
| 	}
 | |
| }
 | |
| 
 | |
| // Recursive case-insensitive lookup function used by n.findCaseInsensitivePath
 | |
| func (n *node) findCaseInsensitivePathRec(path string, ciPath []byte, rb [4]byte, fixTrailingSlash bool) []byte {
 | |
| 	npLen := len(n.path)
 | |
| 
 | |
| walk: // Outer loop for walking the tree
 | |
| 	for len(path) >= npLen && (npLen == 0 || strings.EqualFold(path[1:npLen], n.path[1:])) {
 | |
| 		// Add common prefix to result
 | |
| 		oldPath := path
 | |
| 		path = path[npLen:]
 | |
| 		ciPath = append(ciPath, n.path...)
 | |
| 
 | |
| 		if len(path) == 0 {
 | |
| 			// We should have reached the node containing the handle.
 | |
| 			// Check if this node has a handle registered.
 | |
| 			if n.handlers != nil {
 | |
| 				return ciPath
 | |
| 			}
 | |
| 
 | |
| 			// No handle found.
 | |
| 			// Try to fix the path by adding a trailing slash
 | |
| 			if fixTrailingSlash {
 | |
| 				for i, c := range []byte(n.indices) {
 | |
| 					if c == '/' {
 | |
| 						n = n.children[i]
 | |
| 						if (len(n.path) == 1 && n.handlers != nil) ||
 | |
| 							(n.nType == catchAll && n.children[0].handlers != nil) {
 | |
| 							return append(ciPath, '/')
 | |
| 						}
 | |
| 						return nil
 | |
| 					}
 | |
| 				}
 | |
| 			}
 | |
| 			return nil
 | |
| 		}
 | |
| 
 | |
| 		// If this node does not have a wildcard (param or catchAll) child,
 | |
| 		// we can just look up the next child node and continue to walk down
 | |
| 		// the tree
 | |
| 		if !n.wildChild {
 | |
| 			// Skip rune bytes already processed
 | |
| 			rb = shiftNRuneBytes(rb, npLen)
 | |
| 
 | |
| 			if rb[0] != 0 {
 | |
| 				// Old rune not finished
 | |
| 				idxc := rb[0]
 | |
| 				for i, c := range []byte(n.indices) {
 | |
| 					if c == idxc {
 | |
| 						// continue with child node
 | |
| 						n = n.children[i]
 | |
| 						npLen = len(n.path)
 | |
| 						continue walk
 | |
| 					}
 | |
| 				}
 | |
| 			} else {
 | |
| 				// Process a new rune
 | |
| 				var rv rune
 | |
| 
 | |
| 				// Find rune start.
 | |
| 				// Runes are up to 4 byte long,
 | |
| 				// -4 would definitely be another rune.
 | |
| 				var off int
 | |
| 				for max := min(npLen, 3); off < max; off++ {
 | |
| 					if i := npLen - off; utf8.RuneStart(oldPath[i]) {
 | |
| 						// read rune from cached path
 | |
| 						rv, _ = utf8.DecodeRuneInString(oldPath[i:])
 | |
| 						break
 | |
| 					}
 | |
| 				}
 | |
| 
 | |
| 				// Calculate lowercase bytes of current rune
 | |
| 				lo := unicode.ToLower(rv)
 | |
| 				utf8.EncodeRune(rb[:], lo)
 | |
| 
 | |
| 				// Skip already processed bytes
 | |
| 				rb = shiftNRuneBytes(rb, off)
 | |
| 
 | |
| 				idxc := rb[0]
 | |
| 				for i, c := range []byte(n.indices) {
 | |
| 					// Lowercase matches
 | |
| 					if c == idxc {
 | |
| 						// must use a recursive approach since both the
 | |
| 						// uppercase byte and the lowercase byte might exist
 | |
| 						// as an index
 | |
| 						if out := n.children[i].findCaseInsensitivePathRec(
 | |
| 							path, ciPath, rb, fixTrailingSlash,
 | |
| 						); out != nil {
 | |
| 							return out
 | |
| 						}
 | |
| 						break
 | |
| 					}
 | |
| 				}
 | |
| 
 | |
| 				// If we found no match, the same for the uppercase rune,
 | |
| 				// if it differs
 | |
| 				if up := unicode.ToUpper(rv); up != lo {
 | |
| 					utf8.EncodeRune(rb[:], up)
 | |
| 					rb = shiftNRuneBytes(rb, off)
 | |
| 
 | |
| 					idxc := rb[0]
 | |
| 					for i, c := range []byte(n.indices) {
 | |
| 						// Uppercase matches
 | |
| 						if c == idxc {
 | |
| 							// Continue with child node
 | |
| 							n = n.children[i]
 | |
| 							npLen = len(n.path)
 | |
| 							continue walk
 | |
| 						}
 | |
| 					}
 | |
| 				}
 | |
| 			}
 | |
| 
 | |
| 			// Nothing found. We can recommend to redirect to the same URL
 | |
| 			// without a trailing slash if a leaf exists for that path
 | |
| 			if fixTrailingSlash && path == "/" && n.handlers != nil {
 | |
| 				return ciPath
 | |
| 			}
 | |
| 			return nil
 | |
| 		}
 | |
| 
 | |
| 		n = n.children[0]
 | |
| 		switch n.nType {
 | |
| 		case param:
 | |
| 			// Find param end (either '/' or path end)
 | |
| 			end := 0
 | |
| 			for end < len(path) && path[end] != '/' {
 | |
| 				end++
 | |
| 			}
 | |
| 
 | |
| 			// Add param value to case insensitive path
 | |
| 			ciPath = append(ciPath, path[:end]...)
 | |
| 
 | |
| 			// We need to go deeper!
 | |
| 			if end < len(path) {
 | |
| 				if len(n.children) > 0 {
 | |
| 					// Continue with child node
 | |
| 					n = n.children[0]
 | |
| 					npLen = len(n.path)
 | |
| 					path = path[end:]
 | |
| 					continue
 | |
| 				}
 | |
| 
 | |
| 				// ... but we can't
 | |
| 				if fixTrailingSlash && len(path) == end+1 {
 | |
| 					return ciPath
 | |
| 				}
 | |
| 				return nil
 | |
| 			}
 | |
| 
 | |
| 			if n.handlers != nil {
 | |
| 				return ciPath
 | |
| 			}
 | |
| 
 | |
| 			if fixTrailingSlash && len(n.children) == 1 {
 | |
| 				// No handle found. Check if a handle for this path + a
 | |
| 				// trailing slash exists
 | |
| 				n = n.children[0]
 | |
| 				if n.path == "/" && n.handlers != nil {
 | |
| 					return append(ciPath, '/')
 | |
| 				}
 | |
| 			}
 | |
| 
 | |
| 			return nil
 | |
| 
 | |
| 		case catchAll:
 | |
| 			return append(ciPath, path...)
 | |
| 
 | |
| 		default:
 | |
| 			panic("invalid node type")
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	// Nothing found.
 | |
| 	// Try to fix the path by adding / removing a trailing slash
 | |
| 	if fixTrailingSlash {
 | |
| 		if path == "/" {
 | |
| 			return ciPath
 | |
| 		}
 | |
| 		if len(path)+1 == npLen && n.path[len(path)] == '/' &&
 | |
| 			strings.EqualFold(path[1:], n.path[1:len(path)]) && n.handlers != nil {
 | |
| 			return append(ciPath, n.path...)
 | |
| 		}
 | |
| 	}
 | |
| 	return nil
 | |
| }
 |