diff --git a/src/uucore/src/lib/lib.rs b/src/uucore/src/lib/lib.rs index eb630f53a..c17f14516 100644 --- a/src/uucore/src/lib/lib.rs +++ b/src/uucore/src/lib/lib.rs @@ -25,6 +25,7 @@ mod features; // feature-gated code modules mod mods; // core cross-platform modules // * cross-platform modules +pub use crate::mods::backup_control; pub use crate::mods::coreopts; pub use crate::mods::os; pub use crate::mods::panic; diff --git a/src/uucore/src/lib/mods.rs b/src/uucore/src/lib/mods.rs index 74725e141..2689361a0 100644 --- a/src/uucore/src/lib/mods.rs +++ b/src/uucore/src/lib/mods.rs @@ -1,5 +1,6 @@ // mods ~ cross-platforms modules (core/bundler file) +pub mod backup_control; pub mod coreopts; pub mod os; pub mod panic; diff --git a/src/uucore/src/lib/mods/backup_control.rs b/src/uucore/src/lib/mods/backup_control.rs new file mode 100644 index 000000000..6004ae84d --- /dev/null +++ b/src/uucore/src/lib/mods/backup_control.rs @@ -0,0 +1,97 @@ +use std::{ + env, + path::{Path, PathBuf}, +}; + +pub static BACKUP_CONTROL_VALUES: &[&str] = &[ + "simple", "never", "numbered", "t", "existing", "nil", "none", "off", +]; + +pub static BACKUP_CONTROL_LONG_HELP: &str = "The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX. Here are the version control values: + +none, off + never make backups (even if --backup is given) + +numbered, t + make numbered backups + +existing, nil + numbered if numbered backups exist, simple otherwise + +simple, never + always make simple backups"; + +#[derive(Debug, Clone, Copy, Eq, PartialEq)] +pub enum BackupMode { + NoBackup, + SimpleBackup, + NumberedBackup, + ExistingBackup, +} + +pub fn determine_backup_suffix(supplied_suffix: Option<&str>) -> String { + if let Some(suffix) = supplied_suffix { + String::from(suffix) + } else { + env::var("SIMPLE_BACKUP_SUFFIX").unwrap_or("~".to_owned()) + } +} + +pub fn determine_backup_mode(backup_opt_exists: bool, backup_opt: Option<&str>) -> BackupMode { + if backup_opt_exists { + match backup_opt.map(String::from) { + // default is existing, see: + // https://www.gnu.org/software/coreutils/manual/html_node/Backup-options.html + None => BackupMode::ExistingBackup, + Some(mode) => match &mode[..] { + "simple" | "never" => BackupMode::SimpleBackup, + "numbered" | "t" => BackupMode::NumberedBackup, + "existing" | "nil" => BackupMode::ExistingBackup, + "none" | "off" => BackupMode::NoBackup, + _ => panic!(), // cannot happen as it is managed by clap + }, + } + } else { + BackupMode::NoBackup + } +} + +pub fn get_backup_path( + backup_mode: BackupMode, + backup_path: &Path, + suffix: &str, +) -> Option { + match backup_mode { + BackupMode::NoBackup => None, + BackupMode::SimpleBackup => Some(simple_backup_path(backup_path, suffix)), + BackupMode::NumberedBackup => Some(numbered_backup_path(backup_path)), + BackupMode::ExistingBackup => Some(existing_backup_path(backup_path, suffix)), + } +} + +pub fn simple_backup_path(path: &Path, suffix: &str) -> PathBuf { + let mut p = path.to_string_lossy().into_owned(); + p.push_str(suffix); + PathBuf::from(p) +} + +pub fn numbered_backup_path(path: &Path) -> PathBuf { + for i in 1_u64.. { + let path_str = &format!("{}.~{}~", path.to_string_lossy(), i); + let path = Path::new(path_str); + if !path.exists() { + return path.to_path_buf(); + } + } + panic!("cannot create backup") +} + +pub fn existing_backup_path(path: &Path, suffix: &str) -> PathBuf { + let test_path_str = &format!("{}.~1~", path.to_string_lossy()); + let test_path = Path::new(test_path_str); + if test_path.exists() { + numbered_backup_path(path) + } else { + simple_backup_path(path, suffix) + } +}