Merge 7500b02db5 into 2bfd6b37c1

* start on improving __paginate

* make __paginate more robust

* add __paginate_file

* cleanup __paginate unlinking

libc/runtime/runtime.h

@@ -103,6 +103,7 @@ int verynice(void);
 void __warn_if_powersave(void);
 void _Exit1(int) libcesque wontreturn;
 void __paginate(int, const char *);
+void __paginate_file(int, const char *);
 /* memory management */
 void _weakfree(void *);
 void *_mapanon(size_t) attributeallocsize((1)) mallocesque;

libc/stdio/fgets_unlocked.c

@@ -57,11 +57,7 @@ char *fgets_unlocked(char *s, int size, FILE *f) {
           break;
       } else {
         if ((c = fgetc_unlocked(f)) == -1) {
-          if (ferror_unlocked(f) == EINTR) {
-            continue;
-          } else {
-            break;
-          }
+          break;
         }
         *p++ = c & 255;
         if (c == '\n')

libc/x/paginate.c

@@ -17,42 +17,93 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
+#include "libc/calls/syscall_support-nt.internal.h"
+#include "libc/dce.h"
 #include "libc/intrin/safemacros.internal.h"
 #include "libc/limits.h"
+#include "libc/mem/gc.h"
 #include "libc/runtime/runtime.h"
 #include "libc/str/str.h"
+#include "libc/sysv/consts/o.h"
 #include "libc/temp.h"
+#include "libc/x/x.h"
+
+static char *get_pagerpath(char *pathbuf, size_t pathbufsz) {
+  char *pagerpath;
+  if (strcmp(nulltoempty(getenv("TERM")), "dumb") && isatty(0) && isatty(1) &&
+      ((pagerpath = commandv("less", pathbuf, pathbufsz)) ||
+       (pagerpath = commandv("more", pathbuf, pathbufsz)) ||
+       (pagerpath = commandv("more.exe", pathbuf, pathbufsz)) ||
+       (pagerpath = commandv("more.com", pathbuf, pathbufsz)))) {
+    return pagerpath;
+  }
+  return 0;
+}
+
+static bool run_pager(char *args[hasatleast 3]) {
+  char16_t widepath[PATH_MAX];
+  int n, pid;
+  if (IsWindows() && !strcasecmp(args[0], "/C/Windows/System32/more.com") &&
+      (((n = __mkntpath(args[1], widepath)) == -1) ||
+       !(args[1] = gc(utf16to8(widepath, n, 0))))) {
+    return false;
+  }
+  if ((pid = fork()) != -1) {
+    putenv("LC_ALL=C.UTF-8");
+    putenv("LESSCHARSET=utf-8");
+    putenv("LESS=-RS");
+    if (!pid) {
+      execv(args[0], args);
+      _Exit(127);
+    }
+    waitpid(pid, 0, 0);
+    return true;
+  }
+  return false;
+}
 
 /**
  * Displays wall of text in terminal with pagination.
  */
 void __paginate(int fd, const char *s) {
-  int tfd, pid;
+  int tfd;
   char *args[3] = {0};
   char tmppath[] = "/tmp/paginate.XXXXXX";
   char progpath[PATH_MAX];
-  if (strcmp(nulltoempty(getenv("TERM")), "dumb") && isatty(0) && isatty(1) &&
-      ((args[0] = commandv("less", progpath, sizeof(progpath))) ||
-       (args[0] = commandv("more", progpath, sizeof(progpath))) ||
-       (args[0] = commandv("more.exe", progpath, sizeof(progpath))))) {
+  bool done;
+  if ((args[0] = get_pagerpath(progpath, sizeof(progpath)))) {
     if ((tfd = mkstemp(tmppath)) != -1) {
       write(tfd, s, strlen(s));
       close(tfd);
       args[1] = tmppath;
-      if ((pid = fork()) != -1) {
-        putenv("LC_ALL=C.UTF-8");
-        putenv("LESSCHARSET=utf-8");
-        putenv("LESS=-RS");
-        if (!pid) {
-          execv(args[0], args);
-          _Exit(127);
-        }
-        waitpid(pid, 0, 0);
-        unlink(tmppath);
+      done = run_pager(args);
+      unlink(tmppath);
+      if (done) {
         return;
       }
-      unlink(tmppath);
     }
   }
   write(fd, s, strlen(s));
 }
+
+/**
+ * Displays a file in terminal with pagination
+ */
+void __paginate_file(int fd, const char *path) {
+  char *args[3] = {0};
+  char progpath[PATH_MAX];
+  if ((args[0] = get_pagerpath(progpath, sizeof(progpath)))) {
+    args[1] = (char *)path;
+    if (run_pager(args)) {
+      return;
+    }
+  }
+  int sfd = open(path, O_RDONLY);
+  if (sfd != -1) {
+    ssize_t n;
+    while ((n = read(sfd, progpath, sizeof(progpath)) > 0)) {
+      write(fd, progpath, n);
+    }
+  }
+  close(sfd);
+}

test/libc/stdio/fgets_interrupt_test.c

@@ -0,0 +1,138 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8                               :vi │
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2024 Cadence Ember                                                 │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/isystem/errno.h"
+#include "libc/isystem/sched.h"
+#include "libc/isystem/signal.h"
+#include "libc/isystem/stddef.h"
+#include "libc/isystem/unistd.h"
+#include "libc/stdio/stdio.h"
+#include "libc/testlib/testlib.h"
+
+#define MY_TEST_STRING_1 "He"
+#define MY_TEST_STRING_2 "llo world!"
+
+char buf[20] = {0};
+int pipes[2];
+int pid;
+int got_sigusr1 = 0;
+
+// -=- these get called for each test ------------------------------------------
+
+void sigusr1_handler(int) {
+  got_sigusr1 = 1;
+}
+
+void write_pipe(int send_signal_before_end) {
+  // Set up pipe for writing
+  close(pipes[0]);
+  FILE *stream = fdopen(pipes[1], "w");
+
+  // Start writing the first part of the stream
+  fputs(MY_TEST_STRING_1, stream);
+
+  // Send SIGUSR1 to parent (if we're currently testing that)
+  if (send_signal_before_end) {
+    kill(getppid(), SIGUSR1);
+  }
+
+  // Send rest of stream
+  fputs(MY_TEST_STRING_2, stream);
+  // Close stream - this will cause the parent's fgets to end
+  fclose(stream);
+}
+
+void read_pipe() {
+  // Set up pipe for reading
+  close(pipes[1]);
+  FILE *stream = fdopen(pipes[0], "r");
+
+  // Read with fgets
+  fgets(buf, 20, stream);
+
+  // Tidy up
+  fclose(stream);
+}
+
+// -=- these set up the tests --------------------------------------------------
+
+void SetUpOnce(void) {
+  cpu_set_t set;
+  CPU_ZERO(&set);
+  CPU_SET(1, &set);
+  if (sched_setaffinity(0, sizeof set, &set) == -1) {
+    perror("sched_setaffinity");
+    fprintf(stderr, "single core affinity is needed for test reliability\n");
+    _exit(1);
+  }
+}
+
+void setup_signal_and_pipe(uint64_t sa_flags) {
+  // Set up SIGUSR1 handler
+  struct sigaction sa = {.sa_handler = sigusr1_handler, .sa_flags = sa_flags};
+  if (sigaction(SIGUSR1, &sa, NULL) == -1) {
+    perror("sigaction");
+    _exit(1);
+  }
+  got_sigusr1 = 0;
+
+  // Set up pipe between parent and child
+  if (pipe(pipes) == -1) {
+    perror("pipe");
+    _exit(1);
+  }
+}
+
+// -=- these are the tests -----------------------------------------------------
+
+TEST(fgets_eintr, testThatFgetsReadsFromPipeNormally) {
+  setup_signal_and_pipe(0);  // 0 = no SA_RESTART
+  ASSERT_NE(-1, (pid = fork()));
+  if (!pid) {
+    write_pipe(0);  // 0 = no signal
+    _exit(0);
+  }
+  read_pipe();
+  EXPECT_STREQ(MY_TEST_STRING_1 MY_TEST_STRING_2, buf);
+}
+
+TEST(fgets_eintr, testThatTheSignalInterruptsFgets) {
+  setup_signal_and_pipe(0);  // 0 = no SA_RESTART
+  ASSERT_NE(-1, (pid = fork()));
+  if (!pid) {
+    write_pipe(1);  // 1 = signal
+    _exit(0);
+  }
+  read_pipe();
+  EXPECT_STRNE(MY_TEST_STRING_1 MY_TEST_STRING_2, buf);
+  EXPECT_EQ(EINTR, errno);
+  EXPECT_EQ(1, got_sigusr1);
+}
+
+TEST(fgets_eintr, testThatFgetsRestartsWhenSaRestartIsSet) {
+  setup_signal_and_pipe(SA_RESTART);  // SA_RESTART
+  ASSERT_NE(-1, (pid = fork()));
+  if (!pid) {
+    write_pipe(1);  // 1 = signal
+    _exit(0);
+  }
+  read_pipe();
+  EXPECT_STREQ(MY_TEST_STRING_1 MY_TEST_STRING_2, buf);
+  EXPECT_NE(EINTR, errno);
+  EXPECT_EQ(1, got_sigusr1);
+}