perlmod-macro/src/package.rs

   1 use std::env;
   2
   3 use proc_macro2::{Ident, Span, TokenStream};
   4
   5 use quote::quote;
   6 use syn::punctuated::Punctuated;
   7 use syn::{Error, Meta, Token};
   8
   9 use crate::attribs::ModuleAttrs;
  10
  11 const MODULE_HEAD: &str = r#"
  12 require DynaLoader;
  13
  14 sub bootstrap {
  15     my ($pkg) = @_;
  16     my ($mod_name) = {{LIB_NAME}};
  17     my $bootstrap_name = 'boot_' . ($pkg =~ s/::/__/gr);
  18
  19     my @dirs = (map "-L$_/auto", @INC);
  20     my $mod_file = DynaLoader::dl_findfile("#;
  21
  22 #[cfg(debug_assertions)]
  23 const MODULE_HEAD_DEBUG: &str = r#"'-L./target/debug', "#;
  24
  25 #[cfg(not(debug_assertions))]
  26 const MODULE_HEAD_DEBUG: &str = "";
  27
  28 const MODULE_HEAD_2: &str = r#"@dirs, $mod_name);
  29     die "failed to locate shared library for '$pkg' (lib${mod_name}.so)\n" if !$mod_file;
  30
  31     my $lib = DynaLoader::dl_load_file($mod_file)
  32         or die "failed to load library '$mod_file'\n";
  33
  34     my $sym  = DynaLoader::dl_find_symbol($lib, $bootstrap_name);
  35     die "failed to locate '$bootstrap_name'\n" if !defined $sym;
  36     my $boot = DynaLoader::dl_install_xsub($bootstrap_name, $sym, "src/FIXME.rs");
  37     $boot->();
  38 }
  39
  40 __PACKAGE__->bootstrap;
  41
  42 1;
  43 "#;
  44
  45 struct Export {
  46     rust_name: Ident,
  47     perl_name: Option<Ident>,
  48     xs_name: Ident,
  49     prototype: Option<String>,
  50 }
  51
  52 pub struct Package {
  53     pub attrs: ModuleAttrs,
  54     exported: Vec<Export>,
  55 }
  56
  57 impl Package {
  58     pub fn with_attrs(attr: Punctuated<Meta, Token![,]>) -> Result<Self, Error> {
  59         Ok(Self {
  60             attrs: ModuleAttrs::try_from(attr)?,
  61             exported: Vec::new(),
  62         })
  63     }
  64
  65     pub fn export_named(
  66         &mut self,
  67         rust_name: Ident,
  68         perl_name: Option<Ident>,
  69         xs_name: Ident,
  70         prototype: Option<String>,
  71     ) {
  72         self.exported.push(Export {
  73             rust_name,
  74             perl_name,
  75             xs_name,
  76             prototype,
  77         });
  78     }
  79
  80     pub fn bootstrap_function(&self) -> TokenStream {
  81         let mut newxs = TokenStream::new();
  82         for export in &self.exported {
  83             let perl_name = export.perl_name.as_ref().unwrap_or(&export.rust_name);
  84             let sub_name = format!("{}::{}\0", self.attrs.package_name, perl_name);
  85             let sub_lit = syn::LitByteStr::new(sub_name.as_bytes(), perl_name.span());
  86
  87             let xs_name = &export.xs_name;
  88
  89             let prototype = match export.prototype.as_deref() {
  90                 Some(proto) => quote! {
  91                     concat!(#proto, "\0").as_bytes().as_ptr() as *const i8
  92                 },
  93                 None => quote!(::std::ptr::null()),
  94             };
  95
  96             newxs.extend(quote! {
  97                 RSPL_newXS_flags(
  98                     #sub_lit.as_ptr() as *const i8,
  99                     #xs_name as _,
 100                     concat!(::std::file!(), "\0").as_bytes().as_ptr() as *const i8,
 101                     #prototype,
 102                     0,
 103                 );
 104             });
 105         }
 106
 107         let bootstrap_name = format!("boot_{}", self.attrs.package_name).replace("::", "__");
 108         let bootstrap_ident = Ident::new(&bootstrap_name, Span::call_site());
 109
 110         let boot = match &self.attrs.boot {
 111             Some(boot) => quote! { #boot(); },
 112             None => TokenStream::new(),
 113         };
 114
 115         quote! {
 116             #[no_mangle]
 117             pub extern "C" fn #bootstrap_ident(
 118                 _cv: Option<&::perlmod::ffi::CV>,
 119             ) {
 120                 static ONCE: ::std::sync::Once = ::std::sync::Once::new();
 121                 ONCE.call_once(|| {
 122                     unsafe {
 123                         use ::perlmod::ffi::RSPL_newXS_flags;
 124
 125                         let argmark = ::perlmod::ffi::pop_arg_mark();
 126                         argmark.set_stack();
 127
 128                         #newxs
 129                     }
 130
 131                     #boot
 132                 });
 133             }
 134         }
 135     }
 136
 137     pub fn write(&self) -> Result<(), Error> {
 138         let mut source = format!(
 139             "package {};\n{}{}{}",
 140             self.attrs.package_name, MODULE_HEAD, MODULE_HEAD_DEBUG, MODULE_HEAD_2
 141         );
 142
 143         if let Some(lib) = &self.attrs.lib_name {
 144             source = source.replace("{{LIB_NAME}}", &format!("('{lib}')"));
 145         } else {
 146             let lib_name = get_default_lib_name(Span::call_site())?;
 147             source = source.replace("{{LIB_NAME}}", &format!("('{lib_name}')"));
 148         }
 149
 150         let file_name = self
 151             .attrs
 152             .file_name
 153             .clone()
 154             .unwrap_or_else(|| format!("{}.pm", self.attrs.package_name.replace("::", "/")));
 155
 156         let path = std::path::Path::new(&file_name);
 157         if let Some(parent) = path.parent() {
 158             std::fs::create_dir_all(parent).map_err(io_err)?;
 159         }
 160         std::fs::write(path, source.as_bytes()).map_err(io_err)?;
 161
 162         Ok(())
 163     }
 164
 165     pub fn mangle_package_name(&self) -> String {
 166         self.attrs.mangle_package_name()
 167     }
 168 }
 169
 170 fn io_err<E: ToString>(err: E) -> Error {
 171     Error::new(Span::call_site(), err.to_string())
 172 }
 173
 174 pub fn get_default_lib_name(why: Span) -> Result<String, Error> {
 175     env::var("CARGO_PKG_NAME")
 176         .map(|s| s.replace('-', "_"))
 177         .map_err(|err| {
 178             format_err!(
 179                 why,
 180                 "failed to get CARGO_PKG_NAME environment variable: {}",
 181                 err
 182             )
 183         })
 184 }