alter file fetcher to use mmap where available

3 files changed, 116 insertions, 29 deletions

diff --git a/content/fetchers/file.c b/content/fetchers/file.c
index 4deb93248..abedaa7b3 100644
--- a/content/fetchers/file.c
+++ b/content/fetchers/file.c
@@ -34,9 +34,14 @@
 #include <limits.h>
 #include <stdarg.h>
 
+#include "utils/config.h"
+
+#ifdef HAVE_MMAP
+#include <sys/mman.h>
+#endif
+
 #include <libwapcaplet/libwapcaplet.h>
 
-#include "utils/config.h"
 #include "content/dirlist.h"
 #include "content/fetch.h"
 #include "content/fetchers/file.h"
@@ -249,6 +254,82 @@ fetch_file_process_error_aborted:
 static void fetch_file_process_plain(struct fetch_file_context *ctx,
 				     struct stat *fdstat)
 {
+#ifdef HAVE_MMAP
+	fetch_msg msg;
+	char *buf;
+	size_t buf_size;
+
+	int fd; /**< The file descriptor of the object */
+
+	/* Check if we can just return not modified */
+	if (ctx->file_etag != 0 && ctx->file_etag == fdstat->st_mtime) {
+		fetch_set_http_code(ctx->fetchh, 304);
+		msg.type = FETCH_NOTMODIFIED;
+		fetch_file_send_callback(&msg, ctx);
+		return;
+	}
+
+	fd = open(ctx->path, O_RDONLY);
+	if (fd < 0) {
+		/* process errors as appropriate */
+		fetch_file_process_error(ctx,
+				fetch_file_errno_to_http_code(errno));
+		return;
+	}
+
+	/* set buffer size */
+	buf_size = fdstat->st_size;
+	if (buf_size > FETCH_FILE_MAX_BUF_SIZE)
+		buf_size = FETCH_FILE_MAX_BUF_SIZE;
+
+	/* allocate the buffer storage */
+	buf = mmap(NULL, buf_size, PROT_READ, MAP_SHARED, fd, 0);
+	if (buf == MAP_FAILED) {
+		msg.type = FETCH_ERROR;
+		msg.data.error = "Unable to map memory for file data buffer";
+		fetch_file_send_callback(&msg, ctx);
+		close(fd);
+		return;
+	}
+
+	/* fetch is going to be successful */
+	fetch_set_http_code(ctx->fetchh, 200);
+
+	/* Any callback can result in the fetch being aborted.
+	 * Therefore, we _must_ check for this after _every_ call to
+	 * fetch_file_send_callback().
+	 */
+
+	/* content type */
+	if (fetch_file_send_header(ctx, "Content-Type: %s", 
+			fetch_filetype(ctx->path)))
+		goto fetch_file_process_aborted;
+
+	/* content length */
+	if (fetch_file_send_header(ctx, "Content-Length: %"SSIZET_FMT, fdstat->st_size))
+		goto fetch_file_process_aborted;
+
+	/* create etag */
+	if (fetch_file_send_header(ctx, "ETag: \"%10" PRId64 "\"",
+			(int64_t) fdstat->st_mtime))
+		goto fetch_file_process_aborted;
+
+
+	msg.type = FETCH_DATA;
+	msg.data.header_or_data.buf = (const uint8_t *) buf;
+	msg.data.header_or_data.len = buf_size;
+	fetch_file_send_callback(&msg, ctx);
+
+	if (ctx->aborted == false) {
+		msg.type = FETCH_FINISHED;
+		fetch_file_send_callback(&msg, ctx);
+	}
+
+fetch_file_process_aborted:
+
+	munmap(buf, buf_size);
+	close(fd);
+#else
 	fetch_msg msg;
 	char *buf;
 	size_t buf_size;
@@ -256,7 +337,7 @@ static void fetch_file_process_plain(struct fetch_file_context *ctx,
 	ssize_t tot_read = 0;
 	ssize_t res;
 
-	int fd; /**< The file descriptor of the object */
+	FILE *infile;
 
 	/* Check if we can just return not modified */
 	if (ctx->file_etag != 0 && ctx->file_etag == fdstat->st_mtime) {
@@ -266,8 +347,8 @@ static void fetch_file_process_plain(struct fetch_file_context *ctx,
 		return;
 	}
 
-	fd = open(ctx->path, O_RDONLY | O_BINARY);
-	if (fd < 0) {
+	infile = fopen(ctx->path, "rb");
+	if (infile == NULL) {
 		/* process errors as appropriate */
 		fetch_file_process_error(ctx,
 				fetch_file_errno_to_http_code(errno));
@@ -286,7 +367,7 @@ static void fetch_file_process_plain(struct fetch_file_context *ctx,
 		msg.data.error =
 			"Unable to allocate memory for file data buffer";
 		fetch_file_send_callback(&msg, ctx);
-		close(fd);
+		fclose(infile);
 		return;
 	}
 
@@ -314,21 +395,20 @@ static void fetch_file_process_plain(struct fetch_file_context *ctx,
 
 	/* main data loop */
 	while (tot_read < fdstat->st_size) {
-		res = read(fd, buf, buf_size);
-		if (res == -1) {
-			msg.type = FETCH_ERROR;
-			msg.data.error = "Error reading file";
-			fetch_file_send_callback(&msg, ctx);
-			goto fetch_file_process_aborted;
-		}
-
+		res = fread(buf, 1, buf_size, infile);
 		if (res == 0) {
-			msg.type = FETCH_ERROR;
-			msg.data.error = "Unexpected EOF reading file";
-			fetch_file_send_callback(&msg, ctx);
-			goto fetch_file_process_aborted;
+			if (feof(infile)) {
+				msg.type = FETCH_ERROR;
+				msg.data.error = "Unexpected EOF reading file";
+				fetch_file_send_callback(&msg, ctx);
+				goto fetch_file_process_aborted;
+			} else {
+				msg.type = FETCH_ERROR;
+				msg.data.error = "Error reading file";
+				fetch_file_send_callback(&msg, ctx);
+				goto fetch_file_process_aborted;
+			}
 		}
-
 		tot_read += res;
 
 		msg.type = FETCH_DATA;
@@ -345,8 +425,9 @@ static void fetch_file_process_plain(struct fetch_file_context *ctx,
 
 fetch_file_process_aborted:
 
-	close(fd);
+	fclose(infile);
 	free(buf);
+#endif
 	return;
 }
 
diff --git a/utils/config.h b/utils/config.h
index 60b81967a..76142eeb6 100644
--- a/utils/config.h
+++ b/utils/config.h
@@ -90,6 +90,10 @@ char *realpath(const char *path, char *resolved_path);
 #undef HAVE_STDOUT
 #endif
 
+#define HAVE_MMAP
+#if (defined(_WIN32) || defined(riscos) || defined(__HAIKU__) || defined(__BEOS__) || defined(__amigaos4__) || defined(__AMIGA__))
+#undef HAVE_MMAP
+#endif
 
 /* This section toggles build options on and off.
  * Simply undefine a symbol to turn the relevant feature off.
@@ -127,14 +131,4 @@ char *realpath(const char *path, char *resolved_path);
 	#define NO_IPV6
 #endif
 
-/* windows */
-#if (defined(_WIN32))
-#define SSIZET_FMT "Iu"
-#elif (defined(riscos))
-#define SSIZET_FMT "zd"
-#else
-#define SSIZET_FMT "zd"
-#define O_BINARY 0
-#endif
-
 #endif
diff --git a/utils/utils.h b/utils/utils.h
index 02bf75fea..f3dba449f 100644
--- a/utils/utils.h
+++ b/utils/utils.h
@@ -32,26 +32,38 @@
 #ifndef NOF_ELEMENTS
 #define NOF_ELEMENTS(array) (sizeof(array)/sizeof(*(array)))
 #endif
+
 #ifndef ABS
 #define ABS(x) (((x)>0)?(x):(-(x)))
 #endif
+
 #ifdef __MINT__ /* avoid using GCCs builtin min/max functions */
 #undef min
 #undef max
 #endif
+
 #ifndef min
 #define min(x,y) (((x)<(y))?(x):(y))
 #endif
+
 #ifndef max
 #define max(x,y) (((x)>(y))?(x):(y))
 #endif
+
 #ifndef PRIxPTR
 #define PRIxPTR "x"
 #endif
+
 #ifndef PRId64
 #define PRId64 "lld"
 #endif
 
+#if defined(_WIN32)
+#define SSIZET_FMT "Iu"
+#else
+#define SSIZET_FMT "zd"
+#endif
+
 #if defined(__GNUC__) && (__GNUC__ < 3)
 #define FLEX_ARRAY_LEN_DECL 0
 #else