feat: add --max-rows flag to limit input size

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ on:
 env:
   SQLITE_VERSION: "3490100"
   SQLITE_YEAR: "2025"
-  ZIG_VERSION: "0.15.0"
+  ZIG_VERSION: "0.16.0"
 
 jobs:
   build-and-test:

.github/workflows/release.yml

@@ -8,7 +8,7 @@ on:
 env:
   SQLITE_VERSION: "3490100"
   SQLITE_YEAR: "2025"
-  ZIG_VERSION: "0.15.0"
+  ZIG_VERSION: "0.16.0"
 
 jobs:
   build:

README.md

@@ -173,6 +173,7 @@ $ cat events.csv \
 | `--no-type-inference` | Treat all columns as TEXT (skip auto-detection) |
 | `-H`, `--header` | Print column names as the first output row |
 | `--json` | Output results as a JSON array of objects (mutually exclusive with `-d`, `--tsv`, `-H`) |
+| `--max-rows <n>` | Stop if more than `n` data rows are read (exit 1) |
 | `-h`, `--help` | Show usage help and exit |
 | `-V`, `--version` | Print version and exit |
 

build.zig

@@ -17,7 +17,7 @@ pub fn build(b: *std.Build) void {
         []const u8,
         "version",
         "Override version string (default: from build.zig.zon)",
-    ) orelse "0.2.0";
+    ) orelse "0.0.0-dev";
 
     const exe = b.addExecutable(.{
         .name = "sql-pipe",
@@ -35,8 +35,8 @@ pub fn build(b: *std.Build) void {
     exe.root_module.addOptions("build_options", build_options);
 
     if (bundle_sqlite) {
-        exe.addIncludePath(b.path("lib"));
-        exe.addCSourceFile(.{
+        exe.root_module.addIncludePath(b.path("lib"));
+        exe.root_module.addCSourceFile(.{
             .file = b.path("lib/sqlite3.c"),
             .flags = &.{"-DSQLITE_OMIT_LOAD_EXTENSION=1"},
         });
@@ -230,6 +230,56 @@ pub fn build(b: *std.Build) void {
     test_dup_col_stdout.step.dependOn(b.getInstallStep());
     test_step.dependOn(&test_dup_col_stdout.step);
 
+    // Integration test 20: --max-rows under limit succeeds
+    const test_max_rows_under = b.addSystemCommand(&.{
+        "bash", "-c",
+        \\printf 'name,age\nAlice,30\nBob,25\n' | ./zig-out/bin/sql-pipe --max-rows 5 'SELECT name FROM t ORDER BY name' | diff - <(printf 'Alice\nBob\n')
+    });
+    test_max_rows_under.step.dependOn(b.getInstallStep());
+    test_step.dependOn(&test_max_rows_under.step);
+
+    // Integration test 21: --max-rows limit hit exits 1 with error message
+    const test_max_rows_hit = b.addSystemCommand(&.{
+        "bash", "-c",
+        \\msg=$(printf 'name,age\nAlice,30\nBob,25\nCarol,35\n' | ./zig-out/bin/sql-pipe --max-rows 1 'SELECT * FROM t' 2>&1 >/dev/null; echo "EXIT:$?")
+        \\echo "$msg" | grep -q 'error: input exceeds --max-rows limit (1 rows)' && echo "$msg" | grep -q 'EXIT:1'
+    });
+    test_max_rows_hit.step.dependOn(b.getInstallStep());
+    test_step.dependOn(&test_max_rows_hit.step);
+
+    // Integration test 22: --max-rows 0 exits 1 with error message
+    const test_max_rows_zero = b.addSystemCommand(&.{
+        "bash", "-c",
+        \\msg=$(printf 'name,age\nAlice,30\n' | ./zig-out/bin/sql-pipe --max-rows 0 'SELECT * FROM t' 2>&1 >/dev/null; echo "EXIT:$?")
+        \\echo "$msg" | grep -q 'error: --max-rows must be a positive integer' && echo "$msg" | grep -q 'EXIT:1'
+    });
+    test_max_rows_zero.step.dependOn(b.getInstallStep());
+    test_step.dependOn(&test_max_rows_zero.step);
+
+    // Integration test 23: --max-rows=5 (equals form) succeeds
+    const test_max_rows_equals = b.addSystemCommand(&.{
+        "bash", "-c",
+        \\printf 'name,age\nAlice,30\nBob,25\n' | ./zig-out/bin/sql-pipe --max-rows=5 'SELECT name FROM t ORDER BY name' | diff - <(printf 'Alice\nBob\n')
+    });
+    test_max_rows_equals.step.dependOn(b.getInstallStep());
+    test_step.dependOn(&test_max_rows_equals.step);
+
+    // Integration test 24: --max-rows with non-numeric value exits 1
+    const test_max_rows_nan = b.addSystemCommand(&.{
+        "bash", "-c",
+        \\printf 'name,age\nAlice,30\n' | ./zig-out/bin/sql-pipe --max-rows abc 'SELECT * FROM t' 2>&1 >/dev/null; test $? -eq 1
+    });
+    test_max_rows_nan.step.dependOn(b.getInstallStep());
+    test_step.dependOn(&test_max_rows_nan.step);
+
+    // Integration test 25: --no-type-inference --max-rows 1 hits limit and exits 1
+    const test_max_rows_streaming = b.addSystemCommand(&.{
+        "bash", "-c",
+        \\msg=$(printf 'name,age\nAlice,30\nBob,25\n' | ./zig-out/bin/sql-pipe --no-type-inference --max-rows 1 'SELECT * FROM t' 2>&1 >/dev/null; echo "EXIT:$?") && echo "$msg" | grep -q 'EXIT:1'
+    });
+    test_max_rows_streaming.step.dependOn(b.getInstallStep());
+    test_step.dependOn(&test_max_rows_streaming.step);
+
     // Unit tests for the RFC 4180 CSV parser (src/csv.zig)
     const unit_tests = b.addTest(.{
         .root_module = b.createModule(.{

build.zig.zon

@@ -1,8 +1,8 @@
 .{
     .name = .sql_pipe,
-    .version = "0.2.0",
+    .version = "0.0.0-dev",
     .fingerprint = 0xf649b9ac95d768ab,
-    .minimum_zig_version = "0.15.0",
+    .minimum_zig_version = "0.16.0",
     .paths = .{"."},
     .dependencies = .{},
 }

docs/sql-pipe.1.scd

@@ -52,6 +52,11 @@ OPTIONS
 		number, or null). Mutually exclusive with *--delimiter*, *--tsv*, and
 		*--header*.
 
+	*--max-rows* <n>
+		Stop reading input after inserting <n> data rows and exit with
+		code 1 and an error message. Use this to guard against
+		accidentally piping extremely large files into memory.
+
 	*-h, --help*
 		Print the help message and exit with code 0.