RFC: Add optional support for building against the system library using pkg-config.

.github/workflows/rust.yml

@@ -11,9 +11,9 @@ jobs:
         shell: bash
       - run: ci/set_rust_version.bash ${{ matrix.channel }} ${{ matrix.target }}
         shell: bash
-      - run: ci/build.bash cargo ${{ matrix.target }}
+      - run: ci/build.bash cargo ${{ matrix.target }} vendor
         shell: bash
-      - run: ci/test.bash cargo ${{ matrix.target }}
+      - run: ci/test.bash cargo ${{ matrix.target }} vendor
         shell: bash
 
     strategy:
@@ -30,8 +30,8 @@ jobs:
       - uses: actions/checkout@v2
       - run: git submodule update --init
       - run: ci/set_rust_version.bash ${{ matrix.channel }} ${{ matrix.target }}
-      - run: ci/build.bash cargo ${{ matrix.target }}
-      - run: ci/test.bash cargo ${{ matrix.target }}
+      - run: ci/build.bash cargo ${{ matrix.target }} vendor
+      - run: ci/test.bash cargo ${{ matrix.target }} vendor
 
     strategy:
       fail-fast: false
@@ -45,6 +45,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - run: git submodule update --init
+      - run: sudo apt-get update && sudo apt-get install -yqq libqpdf-dev
       - run: ci/set_rust_version.bash ${{ matrix.channel }} ${{ matrix.target }}
       - run: ci/build.bash cargo ${{ matrix.target }}
       - run: ci/test.bash cargo ${{ matrix.target }}

README.md

@@ -16,6 +16,12 @@ Tested on the following targets:
 
 The prebuilt bindings for those targets are included in the source tree.
 
+By default, `pkg-config` will be used to link against the system library `libqpdf`.
+
+If the `vendored` feature is enabled, a vendored source tree of qpdf is built and linked statically.
+
+The `legacy` feature enables bindings to the r2/3/4 encryption options which are available in qpdf 10.x but not 11.x.
+
 ## Usage example
 
 ```rust,no_run

ci/build.bash

@@ -6,16 +6,22 @@ source ci/common.bash
 
 # $1 {path} = Path to cross/cargo executable
 CROSS=$1
-# $1 {string} = <Target Triple>
+# $2 {string} = <Target Triple>
 TARGET_TRIPLE=$2
-# $3 {boolean} = Whether or not building for release or not.
-RELEASE_BUILD=$3
+# $3 {boolean} = Whether to use vendored sources.
+VENDOR=$3
+# $4 {boolean} = Whether or not building for release or not.
+RELEASE_BUILD=$4
 
 required_arg $CROSS 'CROSS'
 required_arg $TARGET_TRIPLE '<Target Triple>'
 
+if [ -n "$VENDOR" ]; then
+    VENDOR="--features vendored"
+fi
+
 if [ -z "$RELEASE_BUILD" ]; then
-    $CROSS build --target $TARGET_TRIPLE --workspace
+    $CROSS build --target $TARGET_TRIPLE $VENDOR --workspace
     $CROSS build --target $TARGET_TRIPLE --all-features --workspace
 else
     $CROSS build --target $TARGET_TRIPLE --all-features --release --workspace

ci/test.bash

@@ -6,11 +6,17 @@ source ci/common.bash
 
 # $1 {path} = Path to cross/cargo executable
 CROSS=$1
-# $1 {string} = <Target Triple>
+# $2 {string} = <Target Triple>
 TARGET_TRIPLE=$2
+# $3 {boolean} = Whether to use vendored sources.
+VENDOR=$3
 
 required_arg $CROSS 'CROSS'
 required_arg $TARGET_TRIPLE '<Target Triple>'
 
-$CROSS test --target $TARGET_TRIPLE --workspace
+if [ -n "$VENDOR" ]; then
+    VENDOR="--features vendored"
+fi
+
+$CROSS test --target $TARGET_TRIPLE $VENDOR --workspace
 $CROSS build --target $TARGET_TRIPLE --all-features --workspace

qpdf-rs/Cargo.toml

@@ -13,3 +13,7 @@ license.workspace = true
 [dependencies]
 qpdf-sys = { path = "../qpdf-sys", version = "0.1" }
 libc = "0.2"
+
+[features]
+vendored = ["qpdf-sys/vendored"]
+legacy = []

qpdf-rs/src/writer.rs

@@ -84,10 +84,13 @@ pub struct EncryptionParamsR6 {
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub enum EncryptionParams {
     /// R2 level, any PDF version
+    #[cfg(feature = "legacy")]
     R2(EncryptionParamsR2),
     /// R3 level, PDF version >= 1.4
+    #[cfg(feature = "legacy")]
     R3(EncryptionParamsR3),
     /// R4 level, PDF version >= 1.5
+    #[cfg(feature = "legacy")]
     R4(EncryptionParamsR4),
     /// R6 level, PDF version >= 1.7
     R6(EncryptionParamsR6),
@@ -195,6 +198,7 @@ impl QPdfWriter {
 
     fn set_encryption_params(&self, params: &EncryptionParams) -> Result<()> {
         match params {
+            #[cfg(feature = "legacy")]
             EncryptionParams::R2(r2) => {
                 let user_password = CString::new(r2.user_password.as_str())?;
                 let owner_password = CString::new(r2.owner_password.as_str())?;
@@ -212,6 +216,7 @@ impl QPdfWriter {
                     })?;
                 }
             }
+            #[cfg(feature = "legacy")]
             EncryptionParams::R3(r3) => {
                 let user_password = CString::new(r3.user_password.as_str())?;
                 let owner_password = CString::new(r3.owner_password.as_str())?;
@@ -232,6 +237,7 @@ impl QPdfWriter {
                     })?;
                 }
             }
+            #[cfg(feature = "legacy")]
             EncryptionParams::R4(r4) => {
                 let user_password = CString::new(r4.user_password.as_str())?;
                 let owner_password = CString::new(r4.owner_password.as_str())?;

qpdf-rs/tests/test_qpdf.rs

@@ -1,6 +1,5 @@
 use std::collections::HashSet;
 
-use qpdf::scalar::QPdfScalar;
 use qpdf::*;
 
 fn load_pdf() -> QPdf {
@@ -14,8 +13,8 @@ fn load_pdf_from_memory() -> QPdf {
 
 #[test]
 fn test_qpdf_version() {
-    assert_eq!(QPdf::library_version(), "10.6.3");
-    println!("{}", QPdf::library_version());
+    let version = dbg!(QPdf::library_version());
+    assert!(!version.is_empty());
 }
 
 #[test]
@@ -294,6 +293,7 @@ fn test_pdf_encrypted_write(params: EncryptionParams) {
     assert!(qpdf.is_err());
 }
 
+#[cfg(feature = "legacy")]
 #[test]
 fn test_pdf_encrypted_r2_write() {
     test_pdf_encrypted_write(EncryptionParams::R2(EncryptionParamsR2 {
@@ -306,6 +306,7 @@ fn test_pdf_encrypted_r2_write() {
     }))
 }
 
+#[cfg(feature = "legacy")]
 #[test]
 fn test_pdf_encrypted_r3_write() {
     test_pdf_encrypted_write(EncryptionParams::R3(EncryptionParamsR3 {
@@ -321,6 +322,7 @@ fn test_pdf_encrypted_r3_write() {
     }))
 }
 
+#[cfg(feature = "legacy")]
 #[test]
 fn test_pdf_encrypted_r4_write() {
     test_pdf_encrypted_write(EncryptionParams::R4(EncryptionParamsR4 {

qpdf-sys/Cargo.toml

@@ -18,5 +18,9 @@ exclude = [
 ]
 
 [build-dependencies]
-cc = { version = "1",  features = ["parallel"] }
+cc = { version = "1", features = ["parallel"], optional = true }
 bindgen = "0.69"
+pkg-config = "0.3"
+
+[features]
+vendored = ["dep:cc"]

qpdf-sys/build.rs

@@ -1,5 +1,6 @@
 use std::{env, path::PathBuf};
 
+#[cfg(feature = "vendored")]
 const ZLIB_SRC: &[&str] = &[
     "adler32.c",
     "compress.c",
@@ -14,6 +15,7 @@ const ZLIB_SRC: &[&str] = &[
     "zutil.c",
 ];
 
+#[cfg(feature = "vendored")]
 const JPEG_SRC: &[&str] = &[
     "jaricom.c",
     "jcapimin.c",
@@ -63,6 +65,7 @@ const JPEG_SRC: &[&str] = &[
     "jutils.c",
 ];
 
+#[cfg(feature = "vendored")]
 const QPDF_SRC: &[&str] = &[
     "AES_PDF_native.cc",
     "BitStream.cc",
@@ -155,6 +158,7 @@ const QPDF_SRC: &[&str] = &[
     "SparseOHArray.cc",
 ];
 
+#[cfg(feature = "vendored")]
 fn base_build() -> cc::Build {
     let root = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
     let mut build = cc::Build::new();
@@ -167,10 +171,12 @@ fn base_build() -> cc::Build {
     build
 }
 
+#[cfg(feature = "vendored")]
 fn is_msvc() -> bool {
     env::var("TARGET").unwrap().ends_with("-msvc")
 }
 
+#[cfg(feature = "vendored")]
 fn build_cc(name: &str, dir: &str, files: &[&str]) {
     let root = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
     let path = root.join(dir);
@@ -188,6 +194,7 @@ fn build_cc(name: &str, dir: &str, files: &[&str]) {
         .compile(name);
 }
 
+#[cfg(feature = "vendored")]
 fn build_qpdf() {
     let root = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
     let cpp_flags: &[&str] = if is_msvc() {
@@ -218,6 +225,7 @@ fn build_qpdf() {
     build_cc("sha2", "qpdf/libqpdf", &["sha2.c", "sha2big.c"]);
 }
 
+#[cfg(feature = "vendored")]
 fn build_bindings() {
     let root = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
     let out_path = PathBuf::from(env::var("OUT_DIR").unwrap()).join("bindings.rs");
@@ -240,9 +248,45 @@ fn build_bindings() {
     }
 }
 
+#[cfg(feature = "vendored")]
 fn main() {
     build_bindings();
     build_cc("zlib", "zlib-1.2.11", ZLIB_SRC);
     build_cc("jpeg", "jpeg-9d", JPEG_SRC);
     build_qpdf();
 }
+
+#[cfg(not(feature = "vendored"))]
+fn main() {
+    let lib = pkg_config::Config::new()
+        .atleast_version("10.6.3")
+        .probe("libqpdf")
+        .unwrap();
+
+    let mut builder = bindgen::builder();
+
+    for path in lib.include_paths {
+        builder = builder.clang_arg(format!("-I{}", path.to_str().unwrap()));
+
+        let header_path = path.join("qpdf/qpdf-c.h");
+        if header_path.exists() {
+            builder = builder.header(header_path.into_os_string().into_string().unwrap());
+        }
+    }
+
+    for (key, val) in lib.defines {
+        builder = builder.clang_arg(match val {
+            Some(val) => format!("-D{}={}", key, val),
+            None => format!("-D{}", key),
+        });
+    }
+
+    let bindings = builder
+        .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
+        .generate()
+        .unwrap();
+
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap()).join("bindings.rs");
+
+    bindings.write_to_file(&out_path).unwrap();
+}