Split oversized runtime, sandbox, and interactive add files into focused helpers

2026-05-18 21:49:43 -05:00
parent ed0b81e587
commit bea901acfe
13 changed files with 1743 additions and 1622 deletions
--- a/app/src/main/java/solutions/tretter/githugandroid/GitProcessRunner.kt
+++ b/app/src/main/java/solutions/tretter/githugandroid/GitProcessRunner.kt
@@ -0,0 +1,183 @@
+package solutions.tretter.githugandroid
+
+import android.content.Context
+import android.system.Os
+import java.io.File
+import java.nio.file.Files
+
+internal class GitProcessRunner(
+    private val context: Context?,
+    private val sandboxesRoot: File,
+) {
+    private companion object {
+        val RequiredGitCommandAliases = listOf(
+            "add",
+            "branch",
+            "checkout",
+            "commit",
+            "commit-tree",
+            "config",
+            "diff",
+            "fetch",
+            "index-pack",
+            "merge",
+            "merge-base",
+            "pack-objects",
+            "pull",
+            "push",
+            "read-tree",
+            "rebase",
+            "receive-pack",
+            "rev-list",
+            "rev-parse",
+            "show-ref",
+            "stash",
+            "status",
+            "symbolic-ref",
+            "unpack-objects",
+            "update-ref",
+            "upload-pack",
+        )
+    }
+
+    fun shellExecutable(): String {
+        return when {
+            context != null -> "/system/bin/sh"
+            File("/bin/sh").exists() -> "/bin/sh"
+            else -> "sh"
+        }
+    }
+
+    fun runGit(
+        binary: File,
+        workingDir: File,
+        arguments: List<String>,
+        environment: Map<String, String> = emptyMap(),
+    ): ProcessExecutionResult {
+        return runProcess(binary, workingDir, arguments, environment)
+    }
+
+    fun runShellProcess(binary: File, workingDir: File, arguments: List<String>): ProcessExecutionResult {
+        return try {
+            val process = ProcessBuilder(listOf(binary.absolutePath) + arguments)
+                .directory(workingDir)
+                .redirectErrorStream(true)
+                .apply {
+                    environment()["HOME"] = workingDir.absolutePath
+                    environment()["LC_ALL"] = "C"
+                }
+                .start()
+
+            val output = process.inputStream.bufferedReader().readLines()
+            val exit = process.waitFor()
+            ProcessExecutionResult(exitCode = exit, outputLines = output)
+        } catch (error: Exception) {
+            ProcessExecutionResult(exitCode = -1, outputLines = listOf("Shell execution failed: ${error.message ?: error::class.java.simpleName}"))
+        }
+    }
+
+    private fun runProcess(
+        binary: File,
+        workingDir: File,
+        arguments: List<String>,
+        extraEnvironment: Map<String, String> = emptyMap(),
+    ): ProcessExecutionResult {
+        return try {
+            val gitExecPath = gitExecDirectory(binary)
+            val process = ProcessBuilder(listOf(binary.absolutePath) + arguments)
+                .directory(workingDir)
+                .redirectErrorStream(true)
+                .apply {
+                    environment()["HOME"] = workingDir.absolutePath
+                    environment()["GIT_EXEC_PATH"] = gitExecPath.absolutePath
+                    environment()["PATH"] = listOfNotNull(
+                        gitExecPath.absolutePath,
+                        System.getenv("PATH")?.takeIf { it.isNotBlank() },
+                    ).joinToString(File.pathSeparator)
+                    environment()["GIT_CONFIG_NOSYSTEM"] = "1"
+                    environment()["GIT_AUTHOR_NAME"] = "GitHug"
+                    environment()["GIT_AUTHOR_EMAIL"] = "githug@example.com"
+                    environment()["GIT_COMMITTER_NAME"] = "GitHug"
+                    environment()["GIT_COMMITTER_EMAIL"] = "githug@example.com"
+                    environment()["LC_ALL"] = "C"
+                    environment().putAll(extraEnvironment)
+                }
+                .start()
+
+            val output = process.inputStream.bufferedReader().readLines()
+            val exit = process.waitFor()
+            ProcessExecutionResult(exitCode = exit, outputLines = output)
+        } catch (error: Exception) {
+            ProcessExecutionResult(exitCode = -1, outputLines = listOf("Native Git execution failed: ${error.message ?: error::class.java.simpleName}"))
+        }
+    }
+
+    private fun gitExecDirectory(binary: File): File {
+        val directory = if (context != null) {
+            File(context.filesDir, "git-exec")
+        } else {
+            File(binary.parentFile ?: binary.absoluteFile.parentFile ?: sandboxesRoot, "git-exec")
+        }
+        refreshGitExecDirectoryIfNeeded(directory, binary)
+        directory.mkdirs()
+
+        File(directory, "git").also { alias ->
+            if (!alias.exists()) {
+                createGitAlias(binary, alias)
+            }
+        }
+        RequiredGitCommandAliases.forEach { command ->
+            listOf("git-$command", command).forEach { aliasName ->
+                val alias = File(directory, aliasName)
+                if (!alias.exists()) {
+                    createGitAlias(binary, alias)
+                }
+            }
+        }
+        return directory
+    }
+
+    private fun refreshGitExecDirectoryIfNeeded(directory: File, binary: File) {
+        val fingerprint = buildString {
+            append(binary.absolutePath)
+            append('\n')
+            append(binary.length())
+            append('\n')
+            append(binary.lastModified())
+        }
+        val stamp = File(directory, ".binary-fingerprint")
+        val previousFingerprint = stamp.takeIf { it.isFile }?.readText()
+        if (previousFingerprint != fingerprint) {
+            directory.deleteRecursively()
+        }
+        directory.mkdirs()
+        stamp.writeText(fingerprint)
+    }
+
+    private fun createGitAlias(binary: File, alias: File) {
+        if (alias.exists() || Files.isSymbolicLink(alias.toPath())) {
+            alias.delete()
+        }
+        if (context != null) {
+            try {
+                Os.symlink(binary.absolutePath, alias.absolutePath)
+                alias.setExecutable(true, false)
+                return
+            } catch (_: Exception) {
+                // Fall through to the portable options below.
+            }
+        }
+
+        try {
+            Files.createSymbolicLink(alias.toPath(), binary.toPath())
+        } catch (_: Exception) {
+            binary.copyTo(alias, overwrite = true)
+        }
+        alias.setExecutable(true, false)
+    }
+}
+
+internal data class ProcessExecutionResult(
+    val exitCode: Int,
+    val outputLines: List<String>,
+)