term: move the term core to subprojects/term

The core now builds, tests, and benchmarks alone, as a Meson subproject
with no dependency on the main tree.

- include/term/ holds term.h and the header-only unicode/. src/ holds
  the core and its private headers. The main tree gets only
  include/term through term_dep, so it cannot reach a private header.
- The term tests, the term benchmarks, the Kitty parser suite, and
  tools/amalgamate.py and tools/generate_unicode.py move with it. The
  tests run as term:<name>.
- The main build passes its -march (arch_flag) and b_ndebug to the
  subproject. A directory configured before this commit needs
  meson configure -Dterm:arch_flag=-march=... once.
- The term tests compile with -UNDEBUG. They do work inside assert.
- The subproject exports term_test_dep with term_api.h, for the main
  tree's render, thumbnail, color, and selection tests.
- The Kitty bridge used struct vector2i and has not compiled since the
  public API redesign. It builds again. 2 of its 14 tests fail: REP
  after a tab, and a cursor report after a resize.
- dirgraph.py drops the term and unicode layers. Its self-test uses pty.
- The symbols test ignores the __odr_asan symbols that ASan adds.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 93 insertions, 0 deletions

diff --git a/benchmarks/hist_bench.c b/benchmarks/hist_bench.c
new file mode 100644
index 0000000..2cf5608
--- /dev/null
+++ b/benchmarks/hist_bench.c
@@ -0,0 +1,93 @@
+#include "hist.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+static double now(void)
+{
+    struct timespec ts;
+    clock_gettime(CLOCK_MONOTONIC, &ts);
+    return ts.tv_sec + ts.tv_nsec * 1e-9;
+}
+
+/* Rows shaped like the term-write-bench lines that scroll into history. */
+static int make_row(const char *name, struct cell *row)
+{
+    struct cell d = { ' ', TERM_COLOR_FG, TERM_COLOR_BG, 0, 0 };
+    int n = 0;
+    if (!strcmp(name, "ascii-row")) {
+        const char *s = "The quick brown fox jumps over the lazy dog. 0123456789";
+        for (; s[n]; n++) {
+            row[n] = d;
+            row[n].c = (uint8_t)s[n];
+        }
+    } else if (!strcmp(name, "cjk-row")) {
+        for (int i = 0; i < 23; i++) {
+            row[n] = d;
+            row[n].c = 0x65e5 + (uint32_t)i;
+            row[n++].flags = CELL_WIDE;
+            row[n] = d;
+            row[n].c = 0;
+            row[n++].flags = CELL_TRAIL;
+        }
+    } else if (!strcmp(name, "colors-row")) {
+        const char *s = "red RGB";
+        for (; s[n]; n++) {
+            row[n] = d;
+            row[n].c = (uint8_t)s[n];
+            if (n < 3)
+                row[n].fg = term_color_index(1);
+            if (n > 3)
+                row[n].fg = term_color_rgb(12, 34, 56);
+        }
+    } else if (!strcmp(name, "fg-char-row")) {
+        for (; n < 120; n++) {
+            row[n] = d;
+            row[n].c = 'a' + (uint32_t)(n % 26);
+            row[n].fg = term_color_rgb((uint8_t)n, (uint8_t)(n * 3), (uint8_t)(n * 7));
+        }
+    }
+    return n;
+}
+
+int main(int argc, char **argv)
+{
+    int iterations = argc > 1 ? atoi(argv[1]) : 10000000;
+    struct hist h;
+    if (!term_hist_init(&h, 10000, 8 * 1024 * 1024)) {
+        fprintf(stderr, "failed to initialize hist\n");
+        return EXIT_FAILURE;
+    }
+
+    const char *line = "abcdefghijklmnopqrstuvwxyz\n";
+    int len = (int)strlen(line);
+    for (int i = 0; i < 10000; i++)
+        term_hist_push_ascii(&h, line, len, NULL, false);
+    double t0 = now();
+    for (int i = 0; i < iterations; i++)
+        term_hist_push_ascii(&h, line, len, NULL, false);
+    double elapsed = now() - t0;
+    printf("%-12s %6.2f ns/line  %.2f GiB/s (%d B/line)\n", "ascii",
+           elapsed * 1e9 / iterations,
+           (double)iterations * len / (1024.0 * 1024.0 * 1024.0) / elapsed, len);
+    term_hist_free(&h);
+
+    static const char *rows[] = { "ascii-row", "cjk-row", "colors-row", "fg-char-row" };
+    for (size_t k = 0; k < sizeof(rows) / sizeof(rows[0]); k++) {
+        struct cell row[128];
+        int n = make_row(rows[k], row);
+        int iters = iterations / 4;
+        if (!term_hist_init(&h, 4096, 0))
+            return EXIT_FAILURE;
+        for (int i = 0; i < 10000; i++)
+            term_hist_push_row(&h, row, n, false, NULL);
+        t0 = now();
+        for (int i = 0; i < iters; i++)
+            term_hist_push_row(&h, row, n, false, NULL);
+        elapsed = now() - t0;
+        printf("%-12s %6.2f ns/row   (%d cells)\n", rows[k], elapsed * 1e9 / iters, n);
+        term_hist_free(&h);
+    }
+    return EXIT_SUCCESS;
+}