build: add script for automatically downloading packages

src/download_packages.sh

@@ -0,0 +1,214 @@
+#!/bin/bash
+
+# List of package URLs to download
+PACKAGE_URLS=(
+    "https://ftp.gnu.org/pub/gnu/libiconv/libiconv-1.17.tar.gz"
+    "https://gmplib.org/download/gmp/gmp-6.3.0.tar.xz"
+    "https://www.mpfr.org/mpfr-current/mpfr-4.2.1.tar.xz"
+    "https://ftp.gnu.org/gnu/gdb/gdb-15.1.tar.xz"
+)
+
+function unpack_tarball() {
+    # Unpack a tarball based on its extension.
+    # Supported extensions: tar, gz, xz.
+    #
+    # Parameters:
+    # $1: tarball
+    #
+    # Returns:
+    # 0: success
+    # 1: failure
+
+    local tarball="$1"
+    local extension="${tarball##*.}"
+
+    if [[ ! -f "$tarball" ]]; then
+        >&2 echo "Error: $tarball does not exist"
+        return 1
+    fi
+
+    case "$extension" in
+        tar | xz)
+            tar xf "$tarball"
+            ;;
+        gz)
+            tar xzf "$tarball"
+            ;;
+        *)
+            >&2 echo "Error: unknown extension $extension"
+            return 1
+            ;;
+    esac
+
+    if [[ $? -ne 0 ]]; then
+        >&2 echo "Error: failed to unpack $tarball"
+        return 1
+    fi
+}
+
+function download_package() {
+    # Download a package. Will skip download if the output file already exists.
+    #
+    # Parameters:
+    # $1: URL of the package
+    # $2: output file
+    #
+    # Returns:
+    # 0: success
+    # 1: failure
+
+    local url="$1"
+    local output="$2"
+
+    if [[ -f "$output" ]]; then
+        >&2 echo "Skipping download: $output already exists"
+        return 0
+    fi
+
+    wget "$url" -O "$output"
+    if [[ $? -ne 0 ]]; then
+        >&2 echo "Error: failed to download $url"
+        return 1
+    fi
+}
+
+function extract_package() {
+    # Extract a package. Will skip extraction if the package directory already exists.
+    #
+    # Parameters:
+    # $1: package tarball
+    # $2: output directory
+    #
+    # Returns:
+    # 0: success
+    # 1: failure
+
+    local tarball="$1"
+    local output_dir="$2"
+    local package_dir="${tarball%.tar*}"
+    local tarball_realpath="$(realpath "$tarball")"
+    local temp_dir="$(mktemp -d)"
+
+    if [[ ! -f "$tarball" ]]; then
+        >&2 echo "Error: $tarball does not exist"
+        return 1
+    fi
+
+    if [[ -d "$output_dir" ]]; then
+        >&2 echo "Skipping extraction: $output_dir already exists"
+        return 0
+    fi
+
+    pushd "$temp_dir" > /dev/null
+
+    unpack_tarball "$tarball_realpath"
+    if [[ $? -ne 0 ]]; then
+        popd > /dev/null
+        return 1
+    fi
+
+    popd > /dev/null
+
+    mv "$temp_dir/$package_dir" "$output_dir"
+    if [[ $? -ne 0 ]]; then
+        return 1
+    fi
+
+    rm -rf "$temp_dir"
+}
+
+function download_and_extract_package() {
+    # Download and extract a package.
+    #
+    # Parameters:
+    # $1: URL of the package
+    # $2: output directory
+    #
+    # Returns:
+    # 0: success
+    # 1: failure
+
+    local url="$1"
+    local output_dir="$2"
+    local tarball=$(basename "$url")
+
+    download_package "$url" "$tarball"
+    if [[ $? -ne 0 ]]; then
+        return 1
+    fi
+
+    extract_package "$tarball" "$output_dir"
+    if [[ $? -ne 0 ]]; then
+        return 1
+    fi
+}
+
+function package_url_to_dir() {
+    # Convert a package URL to a directory name.
+    #
+    # Parameters:
+    # $1: package URL
+    #
+    # Echoes:
+    # The package directory name
+    #
+    # Returns:
+    # 0: success
+    # 1: failure
+
+    local url="$1"
+
+    # The name of the package is the basename of the URL without the version number.
+    local package_dir=$(basename "$url")
+    package_dir="${package_dir%%-*}"
+
+    echo "$package_dir"
+}
+
+function download_gdb_packages() {
+    # Download and extract all required packages for building GDB.
+    #
+    # Parameters:
+    # $1: packages directory
+    #
+    # Returns:
+    # 0: success
+    # 1: failure
+
+    local packages_dir="$1"
+    pushd "$packages_dir"
+
+    # Run downloads in parallel
+    download_pids=()
+
+    for url in "${PACKAGE_URLS[@]}"; do
+        package_dir=$(package_url_to_dir "$url")
+        download_and_extract_package "$url" "$package_dir" &
+        download_pids+=($!)
+    done
+
+    for pid in "${download_pids[@]}"; do
+        wait "$pid"
+        if [[ $? -ne 0 ]]; then
+            popd
+            return 1
+        fi
+    done
+
+    popd
+}
+
+function main() {
+    if [[ $# -ne 1 ]]; then
+        >&2 echo "Usage: $0 <packages_dir>"
+        exit 1
+    fi
+
+    download_gdb_packages "$1"
+    if [[ $? -ne 0 ]]; then
+        >&2 echo "Error: failed to download GDB packages"
+        exit 1
+    fi
+}
+
+main "$@"