fileserver_example: used MHD built-in function for sending files, added comments

author: Evgeny Grin (Karlson2k) <k2k@narod.ru> 2016-11-28 13:36:11 +0300
committer: Evgeny Grin (Karlson2k) <k2k@narod.ru> 2016-12-01 17:42:17 +0300
commit: 938b9b8dae70739c6e629bf144b57b5d6212e6b1 (patch)
tree: da03387929e65b64a6e48eddde2690fbd82ce724 /src/examples
parent: 7f9b98e25631731afd8b853b9f0163dc793a0a57 (diff)
download: libmicrohttpd-938b9b8dae70739c6e629bf144b57b5d6212e6b1.tar.gz
libmicrohttpd-938b9b8dae70739c6e629bf144b57b5d6212e6b1.zip
1 files changed, 25 insertions, 38 deletions
diff --git a/src/examples/fileserver_example.c b/src/examples/fileserver_example.c
index 9a46fba1..4d710575 100644
--- a/src/examples/fileserver_example.c
+++ b/src/examples/fileserver_example.c
@@ -24,31 +24,21 @@
 #include "platform.h"
 #include <microhttpd.h>
+#ifdef HAVE_UNISTD_H
 #include <unistd.h>
+#endif /* HAVE_UNISTD_H */
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif /* HAVE_SYS_STAT_H */
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif /* HAVE_FCNTL_H */
 #define PAGE "<html><head><title>File not found</title></head><body>File not found</body></html>"
+#ifndef S_ISREG
-static ssize_t
+#define S_ISREG(x) (S_IFREG == (x & S_IFREG))
-file_reader (void *cls,
+#endif /* S_ISREG */
-             uint64_t pos,
-             char *buf,
-             size_t max)
-{
-  FILE *file = cls;
-  (void)  fseek (file, pos, SEEK_SET);
-  return fread (buf, 1, max, file);
-}
-static void
-free_callback (void *cls)
-{
-  FILE *file = cls;
-  fclose (file);
-}
 static int
 ahc_echo (void *cls,
@@ -62,7 +52,6 @@ ahc_echo (void *cls,
  static int aptr;
  struct MHD_Response *response;
  int ret;
-  FILE *file;
  int fd;
  struct stat buf;
@@ -76,24 +65,25 @@ ahc_echo (void *cls,
      return MHD_YES;
    }
  *ptr = NULL;                  /* reset when done */
-  file = fopen (&url[1], "rb");
+  /* WARNING: direct usage of url as filename is for example only!
-  if (NULL != file)
+   * NEVER pass received data directly as parameter to file manipulation
+   * functions. Always check validity of data before using.
+   */
+  if (NULL != strstr(url, "../")) /* Very simplified check! */
+    fd = -1; /* Do not allow usage of parent directories. */
+  else
+    fd = open (url + 1, O_RDONLY);
+  if (-1 != fd)
    {
-      fd = fileno (file);
-      if (-1 == fd)
-        {
-          (void) fclose (file);
-          return MHD_NO; /* internal error */
-        }
      if ( (0 != fstat (fd, &buf)) ||
           (! S_ISREG (buf.st_mode)) )
        {
          /* not a regular file, refuse to serve */
-          fclose (file);
+          close (fd);
-          file = NULL;
+          fd = -1;
        }
    }
-  if (NULL == file)
+  if (-1 == fd)
    {
      response = MHD_create_response_from_buffer (strlen (PAGE),
                                                  (void *) PAGE,
@@ -103,13 +93,10 @@ ahc_echo (void *cls,
    }
  else
    {
-      response = MHD_create_response_from_callback (buf.st_size, 32 * 1024,     /* 32k page size */
+      response = MHD_create_response_from_fd64(buf.st_size, fd);
-                                                    &file_reader,
-                                                    file,
-                                                    &free_callback);
      if (NULL == response)
        {
-          fclose (file);
+          close (fd);
          return MHD_NO;
        }
      ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
author	Evgeny Grin (Karlson2k) <k2k@narod.ru>	2016-11-28 13:36:11 +0300
committer	Evgeny Grin (Karlson2k) <k2k@narod.ru>	2016-12-01 17:42:17 +0300
commit	938b9b8dae70739c6e629bf144b57b5d6212e6b1 (patch)
tree	da03387929e65b64a6e48eddde2690fbd82ce724 /src/examples
parent	7f9b98e25631731afd8b853b9f0163dc793a0a57 (diff)
download	libmicrohttpd-938b9b8dae70739c6e629bf144b57b5d6212e6b1.tar.gz libmicrohttpd-938b9b8dae70739c6e629bf144b57b5d6212e6b1.zip

diff --git a/src/examples/fileserver_example.c b/src/examples/fileserver_example.c index 9a46fba1..4d710575 100644 --- a/src/examples/fileserver_example.c +++ b/src/examples/fileserver_example.c
@@ -24,31 +24,21 @@
24		24
25	#include "platform.h"	25	#include "platform.h"
26	#include <microhttpd.h>	26	#include <microhttpd.h>
		27	#ifdef HAVE_UNISTD_H
27	#include <unistd.h>	28	#include <unistd.h>
		29	#endif /* HAVE_UNISTD_H */
		30	#ifdef HAVE_SYS_STAT_H
		31	#include <sys/stat.h>
		32	#endif /* HAVE_SYS_STAT_H */
		33	#ifdef HAVE_FCNTL_H
		34	#include <fcntl.h>
		35	#endif /* HAVE_FCNTL_H */
28		36
29	#define PAGE "<html><head><title>File not found</title></head><body>File not found</body></html>"	37	#define PAGE "<html><head><title>File not found</title></head><body>File not found</body></html>"
30		38
31		39	#ifndef S_ISREG
32	static ssize_t	40	#define S_ISREG(x) (S_IFREG == (x & S_IFREG))
33	file_reader (void *cls,	41	#endif /* S_ISREG */
34	uint64_t pos,
35	char *buf,
36	size_t max)
37	{
38	FILE *file = cls;
39
40	(void) fseek (file, pos, SEEK_SET);
41	return fread (buf, 1, max, file);
42	}
43
44
45	static void
46	free_callback (void *cls)
47	{
48	FILE *file = cls;
49	fclose (file);
50	}
51
52		42
53	static int	43	static int
54	ahc_echo (void *cls,	44	ahc_echo (void *cls,
@@ -62,7 +52,6 @@ ahc_echo (void *cls,
62	static int aptr;	52	static int aptr;
63	struct MHD_Response *response;	53	struct MHD_Response *response;
64	int ret;	54	int ret;
65	FILE *file;
66	int fd;	55	int fd;
67	struct stat buf;	56	struct stat buf;
68		57
@@ -76,24 +65,25 @@ ahc_echo (void *cls,
76	return MHD_YES;	65	return MHD_YES;
77	}	66	}
78	ptr = NULL; / reset when done */	67	ptr = NULL; / reset when done */
79	file = fopen (&url[1], "rb");	68	/* WARNING: direct usage of url as filename is for example only!
80	if (NULL != file)	69	* NEVER pass received data directly as parameter to file manipulation
		70	* functions. Always check validity of data before using.
		71	*/
		72	if (NULL != strstr(url, "../")) /* Very simplified check! */
		73	fd = -1; /* Do not allow usage of parent directories. */
		74	else
		75	fd = open (url + 1, O_RDONLY);
		76	if (-1 != fd)
81	{	77	{
82	fd = fileno (file);
83	if (-1 == fd)
84	{
85	(void) fclose (file);
86	return MHD_NO; /* internal error */
87	}
88	if ( (0 != fstat (fd, &buf)) \|\|	78	if ( (0 != fstat (fd, &buf)) \|\|
89	(! S_ISREG (buf.st_mode)) )	79	(! S_ISREG (buf.st_mode)) )
90	{	80	{
91	/* not a regular file, refuse to serve */	81	/* not a regular file, refuse to serve */
92	fclose (file);	82	close (fd);
93	file = NULL;	83	fd = -1;
94	}	84	}
95	}	85	}
96	if (NULL == file)	86	if (-1 == fd)
97	{	87	{
98	response = MHD_create_response_from_buffer (strlen (PAGE),	88	response = MHD_create_response_from_buffer (strlen (PAGE),
99	(void *) PAGE,	89	(void *) PAGE,
@@ -103,13 +93,10 @@ ahc_echo (void *cls,
103	}	93	}
104	else	94	else
105	{	95	{
106	response = MHD_create_response_from_callback (buf.st_size, 32 * 1024, /* 32k page size */	96	response = MHD_create_response_from_fd64(buf.st_size, fd);
107	&file_reader,
108	file,
109	&free_callback);
110	if (NULL == response)	97	if (NULL == response)
111	{	98	{
112	fclose (file);	99	close (fd);
113	return MHD_NO;	100	return MHD_NO;
114	}	101	}
115	ret = MHD_queue_response (connection, MHD_HTTP_OK, response);	102	ret = MHD_queue_response (connection, MHD_HTTP_OK, response);