rename lib_pathbuffer to lib_tempbuffer

include/limits.h

@@ -130,7 +130,7 @@
 #define _POSIX_PIPE_BUF       512
 #define _POSIX_STREAM_MAX     16
 #define _POSIX_TZNAME_MAX     3
-#define _POSIX2_LINE_MAX      80
+#define _POSIX2_LINE_MAX      CONFIG_LINE_MAX
 
 #ifdef CONFIG_SMALL_MEMORY
 

include/nuttx/lib/lib.h

@@ -31,6 +31,9 @@
 #include <nuttx/fs/fs.h>
 #include <nuttx/kmalloc.h>
 
+#include <limits.h>
+#include <alloca.h>
+
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
@@ -117,10 +120,18 @@ FAR struct file_struct *lib_get_stream(int fd);
 
 unsigned long nrand(unsigned long limit);
 
-/* Functions defined in lib_pathbuffer.c ************************************/
+/* Functions defined in lib_tempbuffer.c ************************************/
+
+#ifdef CONFIG_LIBC_TEMPBUFFER
+FAR char *lib_get_tempbuffer(size_t nbytes);
+void lib_put_tempbuffer(FAR char *buffer);
+#else
+#  define lib_get_tempbuffer(n) alloca(n)
+#  define lib_put_tempbuffer(b)
+#endif
 
-FAR char *lib_get_pathbuffer(void);
-void lib_put_pathbuffer(FAR char *buffer);
+#define lib_get_pathbuffer() lib_get_tempbuffer(PATH_MAX)
+#define lib_put_pathbuffer(b) lib_put_tempbuffer(b)
 
 /* Functions defined in lib_realpath.c **************************************/
 

libs/libc/misc/CMakeLists.txt

@@ -47,8 +47,11 @@ list(
   lib_mkdirat.c
   lib_utimensat.c
   lib_mallopt.c
-  lib_getnprocs.c
-  lib_pathbuffer.c)
+  lib_getnprocs.c)
+
+if(CONFIG_LIBC_TEMPBUFFER)
+  list(APPEND SRCS lib_tempbuffer.c)
+endif()
 
 # Support for platforms that do not have long long types
 

libs/libc/misc/Kconfig

@@ -119,19 +119,30 @@ config LIBC_MEM_FD_VFS_PATH
 	---help---
 		The relative path to where memfd will exist in the tmpfs namespace.
 
-config LIBC_MAX_PATHBUFFER
-	int "Maximum size of a temporary file path buffer array"
+config LIBC_TEMPBUFFER
+	bool "Enable global temp buffer"
+	default !DEFAULT_SMALL
+	---help---
+		Enable this option to enable the global temp buffer, otherwise use stack variables via alloca().
+		If the current platform does not require a large TEMP_MAX_SIZE size support and toolchain supports alloca(),
+		we could turn off this option to improve performance.
+
+if LIBC_TEMPBUFFER
+
+config LIBC_MAX_TEMPBUFFER
+	int "Maximum size of a temporary file temp buffer array"
 	range 0 32
 	default 2
 	---help---
-		This value is the maximum size of the buffer that will hold the full
-		file path.
+		This value is the maximum size of the buffer that will hold the full line.
 
-config LIBC_PATHBUFFER_MALLOC
-	bool "Enable malloc pathbuffer"
+config LIBC_TEMPBUFFER_MALLOC
+	bool "Enable malloc tempbuffer"
 	default y
 	---help---
-		Enable malloc path buffer from the heap when pathbuffer is insufficient.
+		Enable malloc temp buffer from the heap when tempbuffer is insufficient.
+
+endif # LIBC_TEMPBUFFER
 
 config LIBC_BACKTRACE_BUFFSIZE
 	int "The size of backtrace record buffer"

libs/libc/misc/Make.defs

@@ -27,7 +27,11 @@ CSRCS += lib_getrandom.c lib_xorshift128.c lib_tea_encrypt.c lib_tea_decrypt.c
 CSRCS += lib_cxx_initialize.c lib_impure.c lib_memfd.c lib_mutex.c
 CSRCS += lib_fchmodat.c lib_fstatat.c lib_getfullpath.c lib_openat.c
 CSRCS += lib_mkdirat.c lib_utimensat.c lib_mallopt.c
-CSRCS += lib_idr.c lib_getnprocs.c lib_pathbuffer.c
+CSRCS += lib_idr.c lib_getnprocs.c
+
+ifeq ($(CONFIG_LIBC_TEMPBUFFER),y)
+CSRCS += lib_tempbuffer.c
+endif
 
 # Support for platforms that do not have long long types
 

libs/libc/misc/lib_pathbuffer.c → libs/libc/misc/lib_tempbuffer.c

@@ -1,5 +1,5 @@
 /****************************************************************************
- * libs/libc/misc/lib_pathbuffer.c
+ * libs/libc/misc/lib_tempbuffer.c
  *
  * SPDX-License-Identifier: Apache-2.0
  *
@@ -35,25 +35,31 @@
  * Pre-processor definitions
  ****************************************************************************/
 
+#if CONFIG_PATH_MAX > CONFIG_LINE_MAX
+#  define TEMP_MAX_SIZE CONFIG_PATH_MAX
+#else
+#  define TEMP_MAX_SIZE CONFIG_LINE_MAX
+#endif
+
 /****************************************************************************
  * Private Types
  ****************************************************************************/
 
-struct pathbuffer_s
+struct tempbuffer_s
 {
   spinlock_t lock;           /* Lock for the buffer */
   unsigned long free_bitmap; /* Bitmap of free buffer */
-  char buffer[CONFIG_LIBC_MAX_PATHBUFFER][PATH_MAX];
+  char buffer[CONFIG_LIBC_MAX_TEMPBUFFER][TEMP_MAX_SIZE];
 };
 
 /****************************************************************************
  * Private Data
  ****************************************************************************/
 
-static struct pathbuffer_s g_pathbuffer =
+static struct tempbuffer_s g_tempbuffer =
 {
   SP_UNLOCKED,
-  (1u << CONFIG_LIBC_MAX_PATHBUFFER) - 1,
+  (1u << CONFIG_LIBC_MAX_TEMPBUFFER) - 1,
 };
 
 /****************************************************************************
@@ -65,56 +71,59 @@ static struct pathbuffer_s g_pathbuffer =
  ****************************************************************************/
 
 /****************************************************************************
- * Name: lib_get_pathbuffer
+ * Name: lib_get_tempbuffer
  *
  * Description:
- *   The lib_get_pathbuffer() function returns a pointer to a temporary
+ *   The lib_get_tempbuffer() function returns a pointer to a temporary
  *   buffer.  The buffer is allocated from a pool of pre-allocated buffers
  *   and if the pool is exhausted, a new buffer is allocated through
- *   kmm_malloc(). The size of the buffer is PATH_MAX, and must freed by
- *   calling lib_put_pathbuffer().
+ *   kmm_malloc(). The size of the buffer is nbytes, and must freed by
+ *   calling lib_put_tempbuffer().
  *
  * Returned Value:
- *   On success, lib_get_pathbuffer() returns a pointer to a temporary
+ *   On success, lib_get_tempbuffer() returns a pointer to a temporary
  *   buffer.  On failure, NULL is returned.
  *
  ****************************************************************************/
 
-FAR char *lib_get_pathbuffer(void)
+FAR char *lib_get_tempbuffer(size_t nbytes)
 {
   irqstate_t flags;
   int index;
 
-  /* Try to find a free buffer */
-
-  flags = spin_lock_irqsave(&g_pathbuffer.lock);
-  index = ffsl(g_pathbuffer.free_bitmap) - 1;
-  if (index >= 0 && index < CONFIG_LIBC_MAX_PATHBUFFER)
+  if (nbytes <= TEMP_MAX_SIZE)
     {
-      g_pathbuffer.free_bitmap &= ~(1u << index);
-      spin_unlock_irqrestore(&g_pathbuffer.lock, flags);
-      return g_pathbuffer.buffer[index];
+      /* Try to find a free buffer */
+
+      flags = spin_lock_irqsave(&g_tempbuffer.lock);
+      index = ffsl(g_tempbuffer.free_bitmap) - 1;
+      if (index >= 0 && index < CONFIG_LIBC_MAX_TEMPBUFFER)
+        {
+          g_tempbuffer.free_bitmap &= ~(1u << index);
+          spin_unlock_irqrestore(&g_tempbuffer.lock, flags);
+          return g_tempbuffer.buffer[index];
+        }
+
+      spin_unlock_irqrestore(&g_tempbuffer.lock, flags);
     }
 
-  spin_unlock_irqrestore(&g_pathbuffer.lock, flags);
-
   /* If no free buffer is found, allocate a new one if
-   * CONFIG_LIBC_PATHBUFFER_MALLOC is enabled
+   * CONFIG_LIBC_TEMPBUFFER_MALLOC is enabled
    */
 
-#ifdef CONFIG_LIBC_PATHBUFFER_MALLOC
-  return lib_malloc(PATH_MAX);
+#ifdef CONFIG_LIBC_TEMPBUFFER_MALLOC
+  return lib_malloc(nbytes);
 #else
   return NULL;
 #endif
 }
 
 /****************************************************************************
- * Name: lib_put_pathbuffer
+ * Name: lib_put_tempbuffer
  *
  * Description:
- *   The lib_put_pathbuffer() function frees a temporary buffer that was
- *   allocated by lib_get_pathbuffer(). If the buffer was allocated
+ *   The lib_put_tempbuffer() function frees a temporary buffer that was
+ *   allocated by lib_get_tempbuffer(). If the buffer was allocated
  *   dynamically, it is freed by calling kmm_free(). Otherwise, the buffer
  *   is marked as free in the pool of pre-allocated buffers.
  *
@@ -123,25 +132,25 @@ FAR char *lib_get_pathbuffer(void)
  *
  ****************************************************************************/
 
-void lib_put_pathbuffer(FAR char *buffer)
+void lib_put_tempbuffer(FAR char *buffer)
 {
   irqstate_t flags;
   int index;
 
-  index = (buffer - &g_pathbuffer.buffer[0][0]) / PATH_MAX;
-  if (index >= 0 && index < CONFIG_LIBC_MAX_PATHBUFFER)
+  index = (buffer - &g_tempbuffer.buffer[0][0]) / TEMP_MAX_SIZE;
+  if (index >= 0 && index < CONFIG_LIBC_MAX_TEMPBUFFER)
     {
       /* Mark the corresponding bit as free */
 
-      flags = spin_lock_irqsave(&g_pathbuffer.lock);
-      g_pathbuffer.free_bitmap |= 1u << index;
-      spin_unlock_irqrestore(&g_pathbuffer.lock, flags);
+      flags = spin_lock_irqsave(&g_tempbuffer.lock);
+      g_tempbuffer.free_bitmap |= 1u << index;
+      spin_unlock_irqrestore(&g_tempbuffer.lock, flags);
       return;
     }
 
   /* Free the buffer if it was dynamically allocated */
 
-#ifdef CONFIG_LIBC_PATHBUFFER_MALLOC
+#ifdef CONFIG_LIBC_TEMPBUFFER_MALLOC
   lib_free(buffer);
 #endif
 }

sched/Kconfig

@@ -1412,6 +1412,16 @@ config PATH_MAX
 	---help---
 		The maximum size of path name.
 
+config LINE_MAX
+	int "Maximum size of line"
+	default 64 if DEFAULT_SMALL
+	default 80 if !DEFAULT_SMALL
+	---help---
+		The maximum size of line. Unless otherwise noted, the maximum length, in bytes,
+		of a utility's input line (either standard input or another file), when the
+		utility is described as processing text files. The length includes room for
+		the trailing newline.
+
 endmenu # Files and I/O
 
 menuconfig PRIORITY_INHERITANCE