e0f69f36ea
Previously the libgo Makefile explicitly listed the set of files to
compile for each package. For packages that use build tags, this
required a lot of awkward automake conditionals in the Makefile.
This CL changes the build to look at the build tags in the files.
The new shell script libgo/match.sh does the matching. This required
adjusting a lot of build tags, and removing some files that are never
used. I verified that the exact same sets of files are compiled on
amd64 GNU/Linux. I also tested the build on i386 Solaris.
Writing match.sh revealed some bugs in the build tag handling that
already exists, in a slightly different form, in the gotest shell
script. This CL fixes those problems as well.
The old code used automake conditionals to handle systems that were
missing strerror_r and wait4. Rather than deal with those in Go, those
functions are now implemented in runtime/go-nosys.c when necessary, so
the Go code can simply assume that they exist.
The os testsuite looked for dir_unix.go, which was never built for gccgo
and has now been removed. I changed the testsuite to look for dir.go
instead.
Reviewed-on: https://go-review.googlesource.com/25546
From-SVN: r239189
46 lines
946 B
Go
46 lines
946 B
Go
// Copyright 2015 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package strings
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// TODO: implements short string optimization on non amd64 platforms
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// and get rid of strings_amd64.go
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// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
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func Index(s, sep string) int {
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n := len(sep)
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switch {
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case n == 0:
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return 0
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case n == 1:
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return IndexByte(s, sep[0])
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case n == len(s):
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if sep == s {
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return 0
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}
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return -1
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case n > len(s):
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return -1
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}
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// Rabin-Karp search
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hashsep, pow := hashStr(sep)
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var h uint32
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for i := 0; i < n; i++ {
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h = h*primeRK + uint32(s[i])
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}
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if h == hashsep && s[:n] == sep {
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return 0
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}
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for i := n; i < len(s); {
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h *= primeRK
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h += uint32(s[i])
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h -= pow * uint32(s[i-n])
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i++
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if h == hashsep && s[i-n:i] == sep {
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return i - n
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}
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}
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return -1
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}
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