rust_htslib/bcf/index.rs
1use crate::{htslib, utils};
2
3#[derive(Debug)]
4pub struct BcfBuildError {
5 pub msg: String,
6}
7
8/// Index type to build.
9pub enum Type {
10 /// Tabix index
11 Tbx,
12 /// CSI index, with given minimum shift
13 Csi(u32),
14}
15
16impl Type {
17 fn min_shift(&self) -> i32 {
18 match self {
19 Self::Tbx => 0,
20 Self::Csi(x) => *x as i32,
21 }
22 }
23}
24
25impl BcfBuildError {
26 pub fn error_message(error: i32) -> &'static str {
27 match error {
28 -1 => "indexing failed",
29 -2 => "opening @fn failed",
30 -3 => "format not indexable",
31 -4 => "failed to create and/or save the index",
32 _ => "unknown error",
33 }
34 }
35}
36impl std::error::Error for BcfBuildError {}
37
38impl std::fmt::Display for BcfBuildError {
39 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
40 write!(f, "BcfBuildError{{msg: {}}}", self.msg)
41 }
42}
43
44/// Build a bcf or vcf.gz index.
45/// Builds tbi or csi depending on index_type.
46///
47///```
48/// // Index a sorted bcf file with csi.
49/// let bcf_path = concat!(env!("CARGO_MANIFEST_DIR"), "/test/test_multi.bcf");
50/// rust_htslib::bcf::index::build(&bcf_path, Some(&"built_test.csi"), /*n_threads=*/ 4u32, rust_htslib::bcf::index::Type::Csi(14)).expect("Failed to build csi index for bcf file.");
51/// assert!(std::path::Path::new(&"built_test.csi").exists());
52///
53/// // Index a bgzip-compresed vcf file with tabix.
54/// let vcf_path = concat!(env!("CARGO_MANIFEST_DIR"), "/test/test_left.vcf.gz");
55/// rust_htslib::bcf::index::build(&vcf_path, Some(&"built_test_vcf.tbx"), /*n_threads=*/ 4u32, rust_htslib::bcf::index::Type::Tbx).expect("Failed to build tbx index for vcf file.");
56/// assert!(std::path::Path::new(&"built_test_vcf.tbx").exists());
57///
58/// // Cannot build a tbi index for a bcf file: returns an Err(BcfBuildError).
59/// assert!(std::panic::catch_unwind(|| rust_htslib::bcf::index::build(bcf_path, Some("built_test.tbi"), 4u32, rust_htslib::bcf::index::Type::Tbx).unwrap()).is_err());
60///
61/// // Cannot built a csi index for a vcf file: returns an Err(BcfBuildError).
62/// let vcf_path = concat!(env!("CARGO_MANIFEST_DIR"), "/test/test_various.vcf");
63/// assert!(std::panic::catch_unwind(|| rust_htslib::bcf::index::build(&vcf_path, Some(&"built_test_vcf.csi"), /*n_threads=*/ 4u32, rust_htslib::bcf::index::Type::Csi(14)).expect("Failed to build csi index for vcf file.")).is_err());
64///```
65///
66pub fn build<P: AsRef<std::path::Path>>(
67 bcf_path: P,
68 idx_path: Option<P>,
69 n_threads: u32,
70 index_type: Type,
71) -> Result<(), BcfBuildError> {
72 let min_shift = index_type.min_shift();
73 let idx_path_cstr = idx_path.and_then(|x| utils::path_to_cstring(&x));
74 let bcf_path = utils::path_to_cstring(&bcf_path).ok_or(BcfBuildError {
75 msg: format!(
76 "Failed to format bcf_path to cstring: {:?}",
77 bcf_path.as_ref().display()
78 ),
79 })?;
80 let return_code = unsafe {
81 htslib::bcf_index_build3(
82 bcf_path.as_ptr(),
83 idx_path_cstr
84 .as_ref()
85 .map_or(std::ptr::null(), |p| p.as_ptr()),
86 min_shift,
87 n_threads as i32,
88 )
89 };
90 if return_code == 0 {
91 Ok(())
92 } else {
93 Err(BcfBuildError {
94 msg: format!(
95 "Failed to build bcf index. Error: {return_code:?}/{}",
96 BcfBuildError::error_message(return_code)
97 ),
98 })
99 }
100}