feat: add Ubuntu 26.04 (Resolute) support

Add Dockerfile, package script, and CI/build configuration for ubuntu-2604 across all build targets.

builder/Dockerfile.ubuntu-2604

@@ -0,0 +1,31 @@
+FROM ubuntu:resolute
+
+ENV OS_IDENTIFIER ubuntu-2604
+
+RUN set -x \
+  && sed -i "s|Types: deb|Types: deb deb-src|g" /etc/apt/sources.list.d/ubuntu.sources \
+  && export DEBIAN_FRONTEND=noninteractive \
+  && apt update \
+  && apt install -y curl libcurl4-openssl-dev libicu-dev libopenblas0-pthread libpcre2-dev libpcre3-dev unzip wget \
+  && apt build-dep -y r-base
+
+# Install s5cmd for S3 uploads (much faster than AWS CLI)
+RUN ARCH=$(uname -m); if [ "$ARCH" = "x86_64" ]; then S5CMD_ARCH="64bit"; else S5CMD_ARCH="arm64"; fi && \
+    curl -sL "https://github.com/peak/s5cmd/releases/download/v2.3.0/s5cmd_2.3.0_Linux-${S5CMD_ARCH}.tar.gz" | tar xz -C /usr/local/bin s5cmd
+
+RUN curl -LO "https://github.com/goreleaser/nfpm/releases/download/v2.18.1/nfpm_$(dpkg --print-architecture).deb" && \
+    apt install -y "./nfpm_$(dpkg --print-architecture).deb" && \
+    rm "nfpm_$(dpkg --print-architecture).deb"
+
+RUN chmod 0777 /opt
+
+# Override the default pager used by R
+ENV PAGER /usr/bin/pager
+
+# R 3.x requires PCRE2 for Pango support on Ubuntu 26
+ENV INCLUDE_PCRE2_IN_R_3 yes
+
+COPY package.ubuntu-2604 /package.sh
+COPY build.sh .
+COPY patches /patches
+ENTRYPOINT ./build.sh

builder/docker-compose.yml

@@ -35,6 +35,18 @@ services:
     image: r-builds:ubuntu-2404
     volumes:
       - /tmp/ubuntu-2404:/tmp/output/ubuntu-2404
+  ubuntu-2604:
+    command: ./build.sh
+    environment:
+      - R_VERSION=${R_VERSION}
+      - R_INSTALL_PATH=${R_INSTALL_PATH}
+      - LOCAL_STORE=/tmp/output
+    build:
+      context: .
+      dockerfile: Dockerfile.ubuntu-2604
+    image: r-builds:ubuntu-2604
+    volumes:
+      - /tmp/ubuntu-2604:/tmp/output/ubuntu-2604
   alpine-320:
     command: ./build.sh
     environment:

builder/package.ubuntu-2604

@@ -0,0 +1,77 @@
+#!/bin/bash
+
+if [[ ! -d /tmp/output/${OS_IDENTIFIER} ]]; then
+  mkdir -p "/tmp/output/${OS_IDENTIFIER}"
+fi
+
+# R 3.x requires PCRE1. On Ubuntu 26, R 3.x also requires PCRE2 for Pango support.
+pcre_libs='- libpcre2-dev'
+if [[ "${R_VERSION}" =~ ^3 ]]; then
+  pcre_libs='- libpcre2-dev
+- libpcre3-dev'
+fi
+
+deflate_libs='# - libdeflate-dev'
+if grep -q '^LIBS *=.*[-]ldeflate' ${R_INSTALL_PATH}/lib/R/etc/Makeconf; then
+    deflate_libs='- libdeflate-dev'
+fi
+
+cat <<EOF > /tmp/nfpm.yml
+name: r-${R_VERSION}
+version: 1
+version_schema: none
+section: universe/math
+priority: optional
+arch: $(dpkg --print-architecture)
+maintainer: Posit Software, PBC <https://github.com/rstudio/r-builds>
+description: |
+  GNU R statistical computation and graphics system
+vendor: Posit Software, PBC
+homepage: https://www.r-project.org
+license: GPL-2
+deb:
+  fields:
+    Bugs: https://github.com/rstudio/r-builds/issues
+depends:
+- g++
+- gcc
+- gfortran
+- libbz2-dev
+- libc6
+- libcairo2
+- libcurl4t64
+${deflate_libs}
+- libglib2.0-0t64
+- libgomp1
+- libicu-dev
+- libjpeg8
+- liblzma-dev
+- libopenblas-dev
+- libpango-1.0-0
+- libpangocairo-1.0-0
+- libpaper-utils
+${pcre_libs}
+- libpng16-16t64
+- libreadline8t64
+- libtcl8.6
+- libtiff6
+- libtirpc-dev
+- libtk8.6
+- libx11-6
+- libxt6t64
+- make
+- ucf
+- unzip
+- zip
+- zlib1g-dev
+contents:
+- src: ${R_INSTALL_PATH}
+  dst: ${R_INSTALL_PATH}
+EOF
+
+nfpm package \
+  -f /tmp/nfpm.yml \
+  -p deb \
+  -t "/tmp/output/${OS_IDENTIFIER}"
+
+export PKG_FILE=$(ls /tmp/output/${OS_IDENTIFIER}/r-${R_VERSION}*.deb | head -1)