one file permission does not cause failure

fcli-core/fcli-aviator-common/src/main/java/com/fortify/cli/aviator/fpr/remediation/writer/FileWriteCoordinator.java

@@ -151,12 +151,25 @@ public void commitRemediationWrites(String instanceId, Map<Path, PendingFileWrit
             throws RemediationCommitException {
         List<RollbackFileWrite> rollbacks = new ArrayList<>();
         for (PendingFileWrite pendingWrite : pendingWrites.values()) {
+            Path filePath = pendingWrite.filePath();
+            // A permission failure is rejected atomically before any bytes are written, so a file
+            // that's already known unwritable needs no rollback entry at all: attempting one would
+            // just retry the same failing write. Checking this upfront (rather than relying on
+            // Files.write's exception to prove the file was untouched) matters once a write CAN
+            // start: e.g. running out of disk space mid-write can truncate/partially overwrite the
+            // file before failing, so a write that's confirmed writable must be recorded for
+            // rollback before attempting it, not after.
+            if (!Files.isWritable(filePath)) {
+                throw new RemediationCommitException(
+                        "Source code file is not writable: '" + pendingWrite.filename() + "'",
+                        new IOException("File not writable: " + filePath), rollbacks);
+            }
             try {
-                byte[] originalBytes = Files.readAllBytes(pendingWrite.filePath());
-                rollbacks.add(new RollbackFileWrite(pendingWrite.filename(), pendingWrite.filePath(), originalBytes));
+                byte[] originalBytes = Files.readAllBytes(filePath);
+                rollbacks.add(new RollbackFileWrite(pendingWrite.filename(), filePath, originalBytes));
                 LOG.debug("Writing remediation {} to '{}' using staged bytes; encodedBytes={}", instanceId, pendingWrite.filename(),
                         pendingWrite.updatedBytes().length);
-                Files.write(pendingWrite.filePath(), pendingWrite.updatedBytes());
+                Files.write(filePath, pendingWrite.updatedBytes());
             } catch (Exception e) {
                 throw new RemediationCommitException("Error writing source code file '" + pendingWrite.filename() + "'", e, rollbacks);
             }

fcli-core/fcli-aviator-common/src/test/java/com/fortify/cli/aviator/fpr/processor/RemediationProcessorTest.java

@@ -678,6 +678,39 @@ void illegalFilenameIsSkippedAndValidRemediationsStillApply() throws Exception {
         assertEquals("before\nREPLACED\nafter\n", Files.readString(sourceFile));
     }
 
+    /**
+     * A source file whose write fails (e.g., made read-only) must be skipped via
+     * {@code SOURCE_WRITE_FAILED} on its own, not abort the whole batch: the rollback attempt for
+     * that failed write must not itself retry writing to the same permission-denied file, which
+     * previously escalated into a batch-aborting {@code RollbackRemediationException} and caused
+     * every other remediation in the run - even ones touching unrelated, writable files - to fail.
+     */
+    @Test
+    @EnabledOnOs(OS.WINDOWS)
+    void readOnlyFileWriteFailureIsSkippedAndOtherRemediationsStillApply() throws Exception {
+        Path readOnlyFile = writeSourceFile("ReadOnly.java", "before\nTARGET\nafter\n");
+        Path goodFile = writeSourceFile("Good.java", "before\nTARGET\nafter\n");
+        readOnlyFile.toFile().setReadOnly();
+        try {
+            Path fprPath = buildFpr(List.of(
+                new MultiHunkRemediationSpec("blocked", List.of(new FileSpec("ReadOnly.java", List.of(
+                    new HunkSpec(2, 2, 1, 1, "before\ntarget\nafter", "TARGET", "REPLACED"))))),
+                new MultiHunkRemediationSpec("valid", List.of(new FileSpec("Good.java", List.of(
+                    new HunkSpec(2, 2, 1, 1, "before\ntarget\nafter", "TARGET", "REPLACED")))))));
+
+            RemediationMetric metric = apply(fprPath);
+
+            assertEquals(2, metric.totalRemediations());
+            assertEquals(1, metric.appliedRemediations(), "the remediation for the writable file must still be applied");
+            assertEquals(1, metric.skippedRemediations());
+            assertEquals(Map.of("Source file write failed", 1), metric.skippedByReason());
+            assertEquals("before\nTARGET\nafter\n", Files.readString(readOnlyFile));
+            assertEquals("before\nREPLACED\nafter\n", Files.readString(goodFile));
+        } finally {
+            readOnlyFile.toFile().setWritable(true);
+        }
+    }
+
     /**
      * The offset ledger must record where a hunk actually landed via the fuzzy anchor, not where
      * it was declared: {@code relocated} declares line 12 but its context/OriginalCode only exist