From 46a314c40c6cd4220c2fc24268008dd11a9110e4 Mon Sep 17 00:00:00 2001 From: Stefan Majewsky Date: Mon, 10 Jul 2017 21:41:47 +0200 Subject: sketch out first steps of prettyprompt.go --- Makefile | 2 +- main.go | 3 +++ pkg/prompt/buffer.go | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++ pkg/prompt/login.go | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++ pkg/prompt/main.go | 46 ++++++++++++++++++++++++++++++++++++ 5 files changed, 181 insertions(+), 1 deletion(-) create mode 100644 pkg/prompt/buffer.go create mode 100644 pkg/prompt/login.go create mode 100644 pkg/prompt/main.go diff --git a/Makefile b/Makefile index c1e786e..55e4a22 100644 --- a/Makefile +++ b/Makefile @@ -1,7 +1,7 @@ PKG = github.com/majewsky/gofu PREFIX = /usr -APPLETS = rtree +APPLETS = rtree prettyprompt all: build/gofu $(addprefix build/,$(APPLETS)) diff --git a/main.go b/main.go index ea34c2e..cb82eca 100644 --- a/main.go +++ b/main.go @@ -23,6 +23,7 @@ import ( "os" "path/filepath" + "github.com/majewsky/gofu/pkg/prompt" "github.com/majewsky/gofu/pkg/rtree" ) @@ -41,6 +42,8 @@ func execApplet(applet string, args []string, allowGofu bool) int { } switch applet { + case "prettyprompt": + return prompt.Exec() case "rtree": return rtree.Exec(args) default: diff --git a/pkg/prompt/buffer.go b/pkg/prompt/buffer.go new file mode 100644 index 0000000..03aca43 --- /dev/null +++ b/pkg/prompt/buffer.go @@ -0,0 +1,66 @@ +/******************************************************************************* +* +* Copyright 2017 Stefan Majewsky +* +* This program is free software: you can redistribute it and/or modify it under +* the terms of the GNU General Public License as published by the Free Software +* Foundation, either version 3 of the License, or (at your option) any later +* version. +* +* This program is distributed in the hope that it will be useful, but WITHOUT ANY +* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +* A PARTICULAR PURPOSE. See the GNU General Public License for more details. +* +* You should have received a copy of the GNU General Public License along with +* this program. If not, see . +* +*******************************************************************************/ + +package prompt + +import "bytes" + +//LineBuffer wraps bytes.Buffer that measures the length of the displayed text +//(minus ANSI escape sequences). +type LineBuffer struct { + buffer bytes.Buffer + length int +} + +//Bytes returns the complete string (including non-printable characters) in the +//buffer. +func (b *LineBuffer) Bytes() []byte { + return b.buffer.Bytes() +} + +//Length returns the number of printable characters in the buffer. +func (b *LineBuffer) Length() int { + return b.length +} + +//Write implements the io.Writer interface. Use this only for printable +//characters. +func (b *LineBuffer) Write(buf []byte) (n int, err error) { + n, err = b.buffer.Write(buf) + b.length += n + return +} + +//WriteNonprintable works like Write, but bytes written do not count towards +//Length(). +func (b *LineBuffer) WriteNonprintable(buf []byte) (int, error) { + return b.buffer.Write(buf) +} + +//WriteWithColor writes a colored printable string. The color is given as the +//semicolon-separated list of arguments to the ANSI escape sequence SGR, e.g. +//"1;41" for bold with red background. +func (b *LineBuffer) WriteWithColor(text, color string) { + if color == "0" { + b.Write([]byte(text)) + } else { + b.WriteNonprintable([]byte("\x1B[" + color + "m")) + b.Write([]byte(text)) + b.WriteNonprintable([]byte("\x1B[0m")) + } +} diff --git a/pkg/prompt/login.go b/pkg/prompt/login.go new file mode 100644 index 0000000..b5fcebd --- /dev/null +++ b/pkg/prompt/login.go @@ -0,0 +1,65 @@ +/******************************************************************************* +* +* Copyright 2017 Stefan Majewsky +* +* This program is free software: you can redistribute it and/or modify it under +* the terms of the GNU General Public License as published by the Free Software +* Foundation, either version 3 of the License, or (at your option) any later +* version. +* +* This program is distributed in the hope that it will be useful, but WITHOUT ANY +* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +* A PARTICULAR PURPOSE. See the GNU General Public License for more details. +* +* You should have received a copy of the GNU General Public License along with +* this program. If not, see . +* +*******************************************************************************/ + +package prompt + +import "os" + +//#include +//#include +import "C" + +func addLogin(buf *LineBuffer) { + //show user name + userName := getUserName() + commonUser := getenvOrDefault("PRETTYPROMPT_COMMONUSER", "stefan") + if commonUser != userName { + color := "0" + if userName == "root" { + color = "1;41" + } + buf.WriteWithColor(userName, color) + buf.Write([]byte("@")) + } + + //show hostname + hostname, err := os.Hostname() + if err != nil { + handleError(err) + hostname = "" + } + buf.WriteWithColor( + getenvOrDefault("PRETTYPROMPT_HOSTCOLOR", "0;33"), + hostname, + ) + buf.Write([]byte(" ")) +} + +func getUserName() string { + //try to find username via getpwuid(getuid()) + pw, err := C.getpwuid(C.__uid_t(os.Getuid())) + if err == nil { + return C.GoString(pw.pw_name) + } + //fallback to $USER, if set + if name := os.Getenv("USER"); name != "" { + return name + } + handleError(err) + return "" +} diff --git a/pkg/prompt/main.go b/pkg/prompt/main.go new file mode 100644 index 0000000..6b4764a --- /dev/null +++ b/pkg/prompt/main.go @@ -0,0 +1,46 @@ +/******************************************************************************* +* +* Copyright 2017 Stefan Majewsky +* +* This program is free software: you can redistribute it and/or modify it under +* the terms of the GNU General Public License as published by the Free Software +* Foundation, either version 3 of the License, or (at your option) any later +* version. +* +* This program is distributed in the hope that it will be useful, but WITHOUT ANY +* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR +* A PARTICULAR PURPOSE. See the GNU General Public License for more details. +* +* You should have received a copy of the GNU General Public License along with +* this program. If not, see . +* +*******************************************************************************/ + +package prompt + +import "os" + +//Exec executes the prettyprompt applet and returns an exit code (0 for +//success, >0 for error). +func Exec() int { + var buf LineBuffer + addLogin(&buf) + + os.Stdout.Write(buf.Bytes()) + os.Stdout.Write([]byte("\n")) + return 0 +} + +func getenvOrDefault(key, defaultValue string) (value string) { + value = os.Getenv(key) + if value == "" { + value = defaultValue + } + return +} + +func handleError(err error) { + if err != nil { + os.Stderr.Write([]byte("\x1B[1;31mPrompt error: " + err.Error() + "\x1B[0m\n")) + } +} -- cgit v1.3.1