Remove dependency on libc crate

5 files changed, 56 insertions, 33 deletions

diff --git a/Cargo.lock b/Cargo.lock
index ef753cc..4e03b69 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3,14 +3,5 @@
 version = 3
 
 [[package]]
-name = "libc"
-version = "0.2.155"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97b3888a4aecf77e811145cadf6eef5901f4782c53886191b2f693f24761847c"
-
-[[package]]
 name = "textgraph"
-version = "0.1.0"
-dependencies = [
- "libc",
-]
+version = "1.0.0"
diff --git a/Cargo.toml b/Cargo.toml
index 5b85730..240bebb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,13 +1,12 @@
 [package]
 name = "textgraph"
-version = "0.1.0"
+version = "1.0.0"
 edition = "2021"
 
 [features]
 default = ["libc", "ansi"]
 ansi = []
-libc = ["dep:libc"]
+libc = []
 
 [dependencies]
-libc = { version = "0.2.155", optional = true }
 
diff --git a/README.md b/README.md
index b70679b..b456a05 100644
--- a/README.md
+++ b/README.md
@@ -29,6 +29,22 @@ sudo install target/release/textgraph /usr/local/bin/textgraph
 sudo install textgraph.1 /usr/share/man/man1/textgraph.1
 ```
 
+### Features
+
+By default `libc` and `ansi` is enabled.
+
+The `libc` feature makes the program able to get the terminal size,
+and catch signals like SIGINT.
+The last part is needed if you want the program to use the alternate screen
+in filter-mode.
+It does not currently use the `libc`-crate, but it does use c-functions.
+
+The `ansi` feature enables the use of ansi escape codes,
+this is used for manipulating the terminal. 
+Like adding colors to the graph,
+and switching back and fourth from the alternate screen 
+(this will only happen when `libc` also is enabled).
+
 ## Example 1
 Some examples of the different modes, from the same input file with random numbers
 ### Star mode
diff --git a/src/main.rs b/src/main.rs
index 3a0a72c..ab4d5e8 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,12 +1,13 @@
-#[cfg(feature = "libc")]
-use std::io::Write;
 use std::io::{self, BufRead};
 use std::str::FromStr;
 use textgraph::graph::GraphBuilder;
 use textgraph::parseopts::{parseopts, OptsBuilder};
 
-#[cfg(feature = "libc")]
-extern "C" fn handle_sigint(_sig: i32) {
+#[cfg(all(feature = "libc", feature = "ansi"))]
+use std::io::Write;
+
+#[cfg(all(feature = "libc", feature = "ansi"))]
+extern "C" fn handle_sigint(_sig: std::os::raw::c_int) {
     print!("\x1b[?25h");
     print!("\x1B[?1049l");
     io::stdout().flush().unwrap();
@@ -14,21 +15,19 @@ extern "C" fn handle_sigint(_sig: i32) {
 }
 
 /// Set a signalhandler for swapping back to the the main screen on sigint
-#[cfg(feature = "libc")]
+#[cfg(all(feature = "libc", feature = "ansi"))]
 fn set_filter_signalhandler() {
-    let mut sig_action: libc::sigaction = unsafe { std::mem::zeroed() };
-    sig_action.sa_flags = 0;
-    sig_action.sa_sigaction = handle_sigint as usize;
-
     unsafe {
-        let mut signal_set = std::mem::zeroed();
-        libc::sigemptyset(&mut signal_set);
-        sig_action.sa_mask = signal_set;
-
-        libc::sigaction(libc::SIGINT, &sig_action, std::ptr::null_mut());
-        libc::sigaction(libc::SIGKILL, &sig_action, std::ptr::null_mut());
-        libc::sigaction(libc::SIGTSTP, &sig_action, std::ptr::null_mut());
-        libc::sigaction(libc::SIGSTOP, &sig_action, std::ptr::null_mut());
+        let mut action: textgraph::term::SigAction = std::mem::zeroed();
+        action.sa_flags = 0;
+        action.sa_sigaction = handle_sigint as usize;
+
+        textgraph::term::sigemptyset(&mut action.sa_mask);
+        textgraph::term::sigaction(15, &action, std::ptr::null_mut()); // 15 is SIGTERM
+        textgraph::term::sigaction(2, &action, std::ptr::null_mut()); //  2 is SIGINT
+        textgraph::term::sigaction(9, &action, std::ptr::null_mut()); //  9 is SIGKILL
+        textgraph::term::sigaction(20, &action, std::ptr::null_mut()); // 20 is SIGSTP
+        textgraph::term::sigaction(19, &action, std::ptr::null_mut()); // 19 is SIGSTOP
     }
 }
 
@@ -60,7 +59,7 @@ fn build_graph(x_values: &Vec<f64>, y_values: &Vec<f64>, opts: &OptsBuilder) ->
 ///
 /// * `opts` -  textgraph::parseopts::OptBuilder
 fn filter(opts: OptsBuilder) {
-    #[cfg(feature = "libc")]
+    #[cfg(all(feature = "libc", feature = "ansi"))]
     {
         set_filter_signalhandler();
         print!("\x1b[?1049h");
@@ -77,11 +76,11 @@ fn filter(opts: OptsBuilder) {
         let line = line.expect("Could not read...");
 
         let y = f64::from_str(line.as_str());
-        if let Err(_) =  y {
+        if let Err(_) = y {
             print!("Could not parse line as f64.");
             continue;
         }
-        if let Ok(y) =  y {
+        if let Ok(y) = y {
             y_values.push(y);
             x_values.push(i);
         }
diff --git a/src/term.rs b/src/term.rs
index 275ab60..9f2d5e2 100644
--- a/src/term.rs
+++ b/src/term.rs
@@ -28,3 +28,21 @@ pub fn get_terminal_size() -> Result<(u16, u16), Error> {
     }
     Ok((ws.ws_col, ws.ws_row))
 }
+
+#[repr(C)]
+pub struct SigAction {
+    pub sa_sigaction: usize,
+    pub sa_mask: SigSet,
+    pub sa_flags: c_int,
+    pub sa_restorer: Option<unsafe extern "C" fn()>,
+}
+
+#[repr(C)]
+pub struct SigSet {
+    pub __val: [u64; 16],
+}
+
+extern "C" {
+    pub fn sigemptyset(set: *mut SigSet) -> c_int;
+    pub fn sigaction(signum: c_int, act: *const SigAction, oldact: *mut SigAction) -> c_int;
+}