Merged with the default branch.

1 files changed, 130 insertions, 7 deletions

diff --git a/src/os/unix/ngx_errno.c b/src/os/unix/ngx_errno.c
index e787b2377..ca23b2d3f 100644
--- a/src/os/unix/ngx_errno.c
+++ b/src/os/unix/ngx_errno.c
@@ -9,6 +9,49 @@
 #include <ngx_core.h>
 
 
+static ngx_str_t   ngx_unknown_error = ngx_string("Unknown error");
+
+
+#if (NGX_HAVE_STRERRORDESC_NP)
+
+/*
+ * The strerrordesc_np() function, introduced in glibc 2.32, is
+ * async-signal-safe.  This makes it possible to use it directly,
+ * without copying error messages.
+ */
+
+
+u_char *
+ngx_strerror(ngx_err_t err, u_char *errstr, size_t size)
+{
+    size_t       len;
+    const char  *msg;
+
+    msg = strerrordesc_np(err);
+
+    if (msg == NULL) {
+        msg = (char *) ngx_unknown_error.data;
+        len = ngx_unknown_error.len;
+
+    } else {
+        len = ngx_strlen(msg);
+    }
+
+    size = ngx_min(size, len);
+
+    return ngx_cpymem(errstr, msg, size);
+}
+
+
+ngx_int_t
+ngx_strerror_init(void)
+{
+    return NGX_OK;
+}
+
+
+#else
+
 /*
  * The strerror() messages are copied because:
  *
@@ -26,7 +69,8 @@
 
 
 static ngx_str_t  *ngx_sys_errlist;
-static ngx_str_t   ngx_unknown_error = ngx_string("Unknown error");
+static ngx_err_t   ngx_first_error;
+static ngx_err_t   ngx_last_error;
 
 
 u_char *
@@ -34,8 +78,13 @@ ngx_strerror(ngx_err_t err, u_char *errstr, size_t size)
 {
     ngx_str_t  *msg;
 
-    msg = ((ngx_uint_t) err < NGX_SYS_NERR) ? &ngx_sys_errlist[err]:
-                                              &ngx_unknown_error;
+    if (err >= ngx_first_error && err < ngx_last_error) {
+        msg = &ngx_sys_errlist[err - ngx_first_error];
+
+    } else {
+        msg = &ngx_unknown_error;
+    }
+
     size = ngx_min(size, msg->len);
 
     return ngx_cpymem(errstr, msg->data, size);
@@ -50,20 +99,92 @@ ngx_strerror_init(void)
     size_t      len;
     ngx_err_t   err;
 
+#if (NGX_SYS_NERR)
+    ngx_first_error = 0;
+    ngx_last_error = NGX_SYS_NERR;
+
+#elif (EPERM > 1000 && EPERM < 0x7fffffff - 1000)
+
+    /*
+     * If number of errors is not known, and EPERM error code has large
+     * but reasonable value, guess possible error codes based on the error
+     * messages returned by strerror(), starting from EPERM.  Notably,
+     * this covers GNU/Hurd, where errors start at 0x40000001.
+     */
+
+    for (err = EPERM; err > EPERM - 1000; err--) {
+        ngx_set_errno(0);
+        msg = strerror(err);
+
+        if (errno == EINVAL
+            || msg == NULL
+            || strncmp(msg, "Unknown error", 13) == 0)
+        {
+            continue;
+        }
+
+        ngx_first_error = err;
+    }
+
+    for (err = EPERM; err < EPERM + 1000; err++) {
+        ngx_set_errno(0);
+        msg = strerror(err);
+
+        if (errno == EINVAL
+            || msg == NULL
+            || strncmp(msg, "Unknown error", 13) == 0)
+        {
+            continue;
+        }
+
+        ngx_last_error = err + 1;
+    }
+
+#else
+
+    /*
+     * If number of errors is not known, guess it based on the error
+     * messages returned by strerror().
+     */
+
+    ngx_first_error = 0;
+
+    for (err = 0; err < 1000; err++) {
+        ngx_set_errno(0);
+        msg = strerror(err);
+
+        if (errno == EINVAL
+            || msg == NULL
+            || strncmp(msg, "Unknown error", 13) == 0)
+        {
+            continue;
+        }
+
+        ngx_last_error = err + 1;
+    }
+
+#endif
+
     /*
      * ngx_strerror() is not ready to work at this stage, therefore,
      * malloc() is used and possible errors are logged using strerror().
      */
 
-    len = NGX_SYS_NERR * sizeof(ngx_str_t);
+    len = (ngx_last_error - ngx_first_error) * sizeof(ngx_str_t);
 
     ngx_sys_errlist = malloc(len);
     if (ngx_sys_errlist == NULL) {
         goto failed;
     }
 
-    for (err = 0; err < NGX_SYS_NERR; err++) {
+    for (err = ngx_first_error; err < ngx_last_error; err++) {
         msg = strerror(err);
+
+        if (msg == NULL) {
+            ngx_sys_errlist[err - ngx_first_error] = ngx_unknown_error;
+            continue;
+        }
+
         len = ngx_strlen(msg);
 
         p = malloc(len);
@@ -72,8 +193,8 @@ ngx_strerror_init(void)
         }
 
         ngx_memcpy(p, msg, len);
-        ngx_sys_errlist[err].len = len;
-        ngx_sys_errlist[err].data = p;
+        ngx_sys_errlist[err - ngx_first_error].len = len;
+        ngx_sys_errlist[err - ngx_first_error].data = p;
     }
 
     return NGX_OK;
@@ -85,3 +206,5 @@ failed:
 
     return NGX_ERROR;
 }
+
+#endif