main: add short help text

We have accumulated so many options over time that they
no longer fit on the screen.

Display only a useful subset of options to the user unless
they pass "-hh".

1 files changed, 53 insertions, 0 deletions

diff --git a/help.go b/help.go
new file mode 100644
index 0000000..378c380
--- /dev/null
+++ b/help.go
@@ -0,0 +1,53 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/rfjakob/gocryptfs/internal/tlog"
+)
+
+const tUsage = "" +
+	"Usage: " + tlog.ProgramName + " -init|-passwd [OPTIONS] CIPHERDIR\n" +
+	"  or   " + tlog.ProgramName + " [OPTIONS] CIPHERDIR MOUNTPOINT\n"
+
+// helpShort is what gets displayed when passed "-h" or on syntax error.
+func helpShort() {
+	printVersion()
+	fmt.Printf("\n")
+	fmt.Printf(tUsage)
+	fmt.Printf(`
+Common Options (use -hh to show all):
+  -aessiv            Use AES-SIV encryption (with -init)
+  -allow_other       Allow other users to access the mount
+  -config            Custom path to config file
+  -ctlsock           Create control socket at location
+  -extpass           Call external program to prompt for the password
+  -fg                Stay in the foreground
+  -fusedebug         Debug FUSE calls
+  -h, -help          This short help text
+  -hh                Long help text with all options
+  -init              Initialize encrypted directory
+  -masterkey         Mount with explicit master key instead of password
+  -nonempty          Allow mounting over non-empty directory
+  -nosyslog          Do not redirect log messages to syslog
+  -passfile          Read password from file
+  -passwd            Change password
+  -plaintextnames    Do not encrypt file names (with -init)
+  -q, -quiet         Silence informational messages
+  -reverse           Enable reverse mode
+  -ro                Mount read-only
+  -speed             Run crypto speed test
+  -version           Print version information
+  --                 Stop option parsing
+`)
+}
+
+// helpLong gets only displayed on "-hh"
+func helpLong() {
+	printVersion()
+	fmt.Printf("\n")
+	fmt.Printf(tUsage)
+	fmt.Printf("\nOptions:\n")
+	flagSet.PrintDefaults()
+	fmt.Printf("  --\n    	Stop option parsing\n")
+}