Consolidate @cImports into a single c.zig

Which is, AFAIK, a recommended practice. Reduces the number of times
translate-c is being run and (most likely) simplifies a possible future
transition if/when @cImport is thrown out of the language.

Also uses zstd.h instead of my own definitions, mainly because I plan to
use the streaming API as well and those need more definitions.

src/bin_export.zig

@@ -7,9 +7,7 @@ const model = @import("model.zig");
 const sink = @import("sink.zig");
 const util = @import("util.zig");
 const ui = @import("ui.zig");
-
+const c = @import("c.zig").c;
-extern fn ZSTD_compress(dst: ?*anyopaque, dstCapacity: usize, src: ?*const anyopaque, srcSize: usize, compressionLevel: c_int) usize;
-extern fn ZSTD_isError(code: usize) c_uint;
 
 pub const global = struct {
     var fd: std.fs.File = undefined;
@@ -65,9 +63,6 @@ inline fn blockHeader(id: u4, len: u28) [4]u8 { return bigu32((@as(u32, id) << 2
 
 inline fn cborByte(major: CborMajor, arg: u5) u8 { return (@as(u8, @intFromEnum(major)) << 5) | arg; }
 
-// ZSTD_COMPRESSBOUND(), assuming input does not exceed ZSTD_MAX_INPUT_SIZE
-fn compressBound(size: usize) usize { return size + (size>>8) + (if (size < (128<<10)) ((128<<10) - size) >> 11 else 0); }
-
 
 // (Uncompressed) data block size.
 // Start with 64k, then use increasingly larger block sizes as the export file
@@ -100,8 +95,8 @@ pub const Thread = struct {
 
     fn compressZstd(in: []const u8, out: []u8) usize {
         while (true) {
-            const r = ZSTD_compress(out.ptr, out.len, in.ptr, in.len, main.config.complevel);
+            const r = c.ZSTD_compress(out.ptr, out.len, in.ptr, in.len, main.config.complevel);
-            if (ZSTD_isError(r) == 0) return r;
+            if (c.ZSTD_isError(r) == 0) return r;
             ui.oom(); // That *ought* to be the only reason the above call can fail.
         }
     }
@@ -110,7 +105,7 @@ pub const Thread = struct {
         var out = std.ArrayList(u8).init(main.allocator);
         if (t.block_num == std.math.maxInt(u32) or t.off == 0) return out;
 
-        out.ensureTotalCapacityPrecise(12 + compressBound(t.off)) catch unreachable;
+        out.ensureTotalCapacityPrecise(12 + c.ZSTD_COMPRESSBOUND(t.off)) catch unreachable;
         out.items.len = out.capacity;
         const bodylen = compressZstd(t.buf[0..t.off], out.items[8..]);
         out.items.len = 12 + bodylen;

src/bin_reader.zig

@@ -8,9 +8,7 @@ const util = @import("util.zig");
 const sink = @import("sink.zig");
 const ui = @import("ui.zig");
 const bin_export = @import("bin_export.zig");
-
+const c = @import("c.zig").c;
-extern fn ZSTD_decompress(dst: ?*anyopaque, dstCapacity: usize, src: ?*const anyopaque, compressedSize: usize) usize;
-extern fn ZSTD_getFrameContentSize(src: ?*const anyopaque, srcSize: usize) c_ulonglong;
 
 
 const CborMajor = bin_export.CborMajor;
@@ -103,11 +101,11 @@ fn readBlock(num: u32) []const u8 {
         catch |e| ui.die("Error reading from file: {s}\n", .{ui.errorString(e)});
     if (rdlen != buf.len) die();
 
-    const rawlen = ZSTD_getFrameContentSize(buf.ptr, buf.len);
+    const rawlen = c.ZSTD_getFrameContentSize(buf.ptr, buf.len);
     if (rawlen <= 0 or rawlen >= (1<<24)) die();
     block.data = main.allocator.alloc(u8, @intCast(rawlen)) catch unreachable;
 
-    const res = ZSTD_decompress(block.data.ptr, block.data.len, buf.ptr, buf.len);
+    const res = c.ZSTD_decompress(block.data.ptr, block.data.len, buf.ptr, buf.len);
     if (res != block.data.len) ui.die("Error decompressing block {} (expected {} got {})\n", .{ num, block.data.len, res });
 
     return block.data;

src/browser.zig

@@ -9,7 +9,7 @@ const mem_sink = @import("mem_sink.zig");
 const bin_reader = @import("bin_reader.zig");
 const delete = @import("delete.zig");
 const ui = @import("ui.zig");
-const c = @cImport(@cInclude("time.h"));
+const c = @import("c.zig").c;
 const util = @import("util.zig");
 
 // Currently opened directory.
@@ -644,8 +644,8 @@ const info = struct {
     fn keyInput(ch: i32) bool {
         if (entry.?.pack.etype == .link) {
             switch (ch) {
-                '1', 'h', ui.c.KEY_LEFT => { set(entry, .info); return true; },
+                '1', 'h', c.KEY_LEFT => { set(entry, .info); return true; },
-                '2', 'l', ui.c.KEY_RIGHT => { set(entry, .links); return true; },
+                '2', 'l', c.KEY_RIGHT => { set(entry, .links); return true; },
                 else => {},
             }
         }
@@ -802,9 +802,9 @@ const help = struct {
             '1' => tab = .keys,
             '2' => tab = .flags,
             '3' => tab = .about,
-            'h', ui.c.KEY_LEFT => tab = if (tab == .about) .flags else .keys,
+            'h', c.KEY_LEFT => tab = if (tab == .about) .flags else .keys,
-            'l', ui.c.KEY_RIGHT => tab = if (tab == .keys) .flags else .about,
+            'l', c.KEY_RIGHT => tab = if (tab == .keys) .flags else .about,
-            'j', ' ', ui.c.KEY_DOWN, ui.c.KEY_NPAGE => {
+            'j', ' ', c.KEY_DOWN, c.KEY_NPAGE => {
                 const max = switch (tab) {
                     .keys => keys.len/2 - keylines,
                     else => @as(u32, 0),
@@ -812,7 +812,7 @@ const help = struct {
                 if (offset < max)
                     offset += 1;
             },
-            'k', ui.c.KEY_UP, ui.c.KEY_PPAGE => { if (offset > 0) offset -= 1; },
+            'k', c.KEY_UP, c.KEY_PPAGE => { if (offset > 0) offset -= 1; },
             else => state = .main,
         }
     }
@@ -917,16 +917,16 @@ fn sortToggle(col: main.config.SortCol, default_order: main.config.SortOrder) vo
 
 fn keyInputSelection(ch: i32, idx: *usize, len: usize, page: u32) bool {
     switch (ch) {
-        'j', ui.c.KEY_DOWN => {
+        'j', c.KEY_DOWN => {
             if (idx.*+1 < len) idx.* += 1;
         },
-        'k', ui.c.KEY_UP => {
+        'k', c.KEY_UP => {
             if (idx.* > 0) idx.* -= 1;
         },
-        ui.c.KEY_HOME => idx.* = 0,
+        c.KEY_HOME => idx.* = 0,
-        ui.c.KEY_END, ui.c.KEY_LL => idx.* = len -| 1,
+        c.KEY_END, c.KEY_LL => idx.* = len -| 1,
-        ui.c.KEY_PPAGE => idx.* = idx.* -| page,
+        c.KEY_PPAGE => idx.* = idx.* -| page,
-        ui.c.KEY_NPAGE => idx.* = @min(len -| 1, idx.* + page),
+        c.KEY_NPAGE => idx.* = @min(len -| 1, idx.* + page),
         else => return false,
     }
     return true;
@@ -1017,7 +1017,7 @@ pub fn keyInput(ch: i32) void {
         },
 
         // Navigation
-        10, 'l', ui.c.KEY_RIGHT => {
+        10, 'l', c.KEY_RIGHT => {
             if (dir_items.items.len == 0) {
             } else if (dir_items.items[cursor_idx]) |e| {
                 if (e.dir()) |d| {
@@ -1032,7 +1032,7 @@ pub fn keyInput(ch: i32) void {
                 state = .main;
             }
         },
-        'h', '<', ui.c.KEY_BACKSPACE, ui.c.KEY_LEFT => {
+        'h', '<', c.KEY_BACKSPACE, c.KEY_LEFT => {
             if (dir_parents.items.len > 1) {
                 //const h = dir_parent.entry.nameHash();
                 enterParent();

src/c.zig

@@ -0,0 +1,17 @@
+// SPDX-FileCopyrightText: Yorhel <projects@yorhel.nl>
+// SPDX-License-Identifier: MIT
+
+pub const c = @cImport({
+    @cDefine("_XOPEN_SOURCE", "1"); // for wcwidth()
+    @cInclude("stdio.h"); // fopen(), used to initialize ncurses
+    @cInclude("string.h"); // strerror()
+    @cInclude("time.h"); // strftime()
+    @cInclude("wchar.h"); // wcwidth()
+    @cInclude("locale.h"); // setlocale() and localeconv()
+    @cInclude("fnmatch.h"); // fnmatch()
+    if (@import("builtin").os.tag == .linux) {
+        @cInclude("sys/vfs.h"); // statfs()
+    }
+    @cInclude("curses.h");
+    @cInclude("zstd.h");
+});

src/delete.zig

@@ -7,6 +7,7 @@ const model = @import("model.zig");
 const ui = @import("ui.zig");
 const browser = @import("browser.zig");
 const util = @import("util.zig");
+const c = @import("c.zig").c;
 
 var parent: *model.Dir = undefined;
 var entry: *model.Entry = undefined;
@@ -178,11 +179,11 @@ pub fn draw() void {
 pub fn keyInput(ch: i32) void {
     switch (state) {
         .confirm => switch (ch) {
-            'h', ui.c.KEY_LEFT => confirm = switch (confirm) {
+            'h', c.KEY_LEFT => confirm = switch (confirm) {
                 .ignore => .no,
                 else => .yes,
             },
-            'l', ui.c.KEY_RIGHT => confirm = switch (confirm) {
+            'l', c.KEY_RIGHT => confirm = switch (confirm) {
                 .yes => .no,
                 else => .ignore,
             },
@@ -202,11 +203,11 @@ pub fn keyInput(ch: i32) void {
                 main.state = .browse;
         },
         .err => switch (ch) {
-            'h', ui.c.KEY_LEFT => error_option = switch (error_option) {
+            'h', c.KEY_LEFT => error_option = switch (error_option) {
                 .all => .ignore,
                 else => .abort,
             },
-            'l', ui.c.KEY_RIGHT => error_option = switch (error_option) {
+            'l', c.KEY_RIGHT => error_option = switch (error_option) {
                 .abort => .ignore,
                 else => .all,
             },

src/exclude.zig

@@ -3,7 +3,7 @@
 
 const std = @import("std");
 const main = @import("main.zig");
-const c = @cImport(@cInclude("fnmatch.h"));
+const c = @import("c.zig").c;
 
 // Reference:
 //   https://manned.org/glob.7

src/main.zig

@@ -18,7 +18,7 @@ const browser = @import("browser.zig");
 const delete = @import("delete.zig");
 const util = @import("util.zig");
 const exclude = @import("exclude.zig");
-const c = @cImport(@cInclude("locale.h"));
+const c = @import("c.zig").c;
 
 test "imports" {
     _ = model;
@@ -634,14 +634,14 @@ pub fn handleEvent(block: bool, force_draw: bool) void {
     while (ui.oom_threads.load(.monotonic) > 0) ui.oom();
 
     if (block or force_draw or event_delay_timer.read() > config.update_delay) {
-        if (ui.inited) _ = ui.c.erase();
+        if (ui.inited) _ = c.erase();
         switch (state) {
             .scan, .refresh => sink.draw(),
             .browse => browser.draw(),
             .delete => delete.draw(),
             .shell => unreachable,
         }
-        if (ui.inited) _ = ui.c.refresh();
+        if (ui.inited) _ = c.refresh();
         event_delay_timer.reset();
     }
     if (!ui.inited) {

src/scan.zig

@@ -8,13 +8,13 @@ const model = @import("model.zig");
 const sink = @import("sink.zig");
 const ui = @import("ui.zig");
 const exclude = @import("exclude.zig");
-const c_statfs = @cImport(@cInclude("sys/vfs.h"));
+const c = @import("c.zig").c;
 
 
 // This function only works on Linux
 fn isKernfs(dir: std.fs.Dir) bool {
-    var buf: c_statfs.struct_statfs = undefined;
+    var buf: c.struct_statfs = undefined;
-    if (c_statfs.fstatfs(dir.fd, &buf) != 0) return false; // silently ignoring errors isn't too nice.
+    if (c.fstatfs(dir.fd, &buf) != 0) return false; // silently ignoring errors isn't too nice.
     const iskern = switch (util.castTruncate(u32, buf.f_type)) {
         // These numbers are documented in the Linux 'statfs(2)' man page, so I assume they're stable.
         0x42494e4d, // BINFMTFS_MAGIC

src/ui.zig

@@ -6,16 +6,7 @@
 const std = @import("std");
 const main = @import("main.zig");
 const util = @import("util.zig");
-
+const c = @import("c.zig").c;
-pub const c = @cImport({
-    @cDefine("_XOPEN_SOURCE", "1");
-    @cInclude("stdio.h");
-    @cInclude("string.h");
-    @cInclude("curses.h");
-    @cInclude("time.h");
-    @cInclude("wchar.h");
-    @cInclude("locale.h");
-});
 
 pub var inited: bool = false;
 pub var main_thread: std.Thread.Id = undefined;