Add 32-bit versions of open file/close file

Add 32-bit API calls for open file and close file.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

8 files changed, 29 insertions, 51 deletions

diff --git a/com32/include/syslinux/pmapi.h b/com32/include/syslinux/pmapi.h
index 34648e52..5631dcba 100644
--- a/com32/include/syslinux/pmapi.h
+++ b/com32/include/syslinux/pmapi.h
@@ -45,11 +45,19 @@
 struct _DIR_;
 struct dirent;
 
+struct com32_filedata {
+    size_t size;		/* File size */
+    int blocklg2;		/* log2(block size) */
+    uint16_t handle;		/* File handle */
+};
+
 struct com32_pmapi {
     void *(*lmalloc)(size_t);
     void (*lfree)(void *);
 
+    int (*open_file)(const char *, struct com32_filedata *);
     size_t (*read_file)(uint16_t *, void *, size_t);
+    void (*close_file)(uint16_t);
 
     struct _DIR_ *(*opendir)(const char *);
     struct dirent *(*readdir)(struct _DIR_ *);
diff --git a/com32/lib/sys/file.h b/com32/lib/sys/file.h
index 66192fbf..e984f160 100644
--- a/com32/lib/sys/file.h
+++ b/com32/lib/sys/file.h
@@ -39,6 +39,7 @@
 #include <sys/types.h>
 #include <dev.h>
 #include <fcntl.h>
+#include <syslinux/pmapi.h>
 
 /* Device structure; contains the relevant operations */
 
@@ -87,11 +88,8 @@ struct file_info {
 
     /* Structure used for input blocking */
     struct {
-	int blocklg2;		/* Blocksize log 2 */
+	struct com32_filedata fd;
 	size_t offset;		/* Current file offset */
-	size_t length;		/* Total file length */
-	uint16_t filedes;	/* File descriptor */
-	uint16_t _filler;	/* Unused */
 	size_t nbytes;		/* Number of bytes available in buffer */
 	char *datap;		/* Current data pointer */
 	void *pvt;		/* Private pointer for driver */
diff --git a/com32/lib/sys/fileclose.c b/com32/lib/sys/fileclose.c
index e005567e..e2c929f2 100644
--- a/com32/lib/sys/fileclose.c
+++ b/com32/lib/sys/fileclose.c
@@ -38,15 +38,8 @@
 
 int __file_close(struct file_info *fp)
 {
-    com32sys_t regs;
-
-    if (fp->i.filedes) {
-	memset(&regs, 0, sizeof regs);
-	regs.eax.w[0] = 0x0008;	/* Close file */
-	regs.esi.w[0] = fp->i.filedes;
-
-	__com32.cs_intcall(0x22, &regs, NULL);
-    }
+    if (fp->i.fd.handle)
+	__com32.cs_pm->close_file(fp->i.fd.handle);
 
     return 0;
 }
diff --git a/com32/lib/sys/fileread.c b/com32/lib/sys/fileread.c
index cfd49557..aab99c80 100644
--- a/com32/lib/sys/fileread.c
+++ b/com32/lib/sys/fileread.c
@@ -42,8 +42,8 @@ int __file_get_block(struct file_info *fp)
 {
     ssize_t bytes_read;
 
-    bytes_read = __com32.cs_pm->read_file(&fp->i.filedes, fp->i.buf,
-					  MAXBLOCK >> fp->i.blocklg2);
+    bytes_read = __com32.cs_pm->read_file(&fp->i.fd.handle, fp->i.buf,
+					  MAXBLOCK >> fp->i.fd.blocklg2);
     if (!bytes_read) {
 	errno = EIO;
 	return -1;
@@ -62,13 +62,13 @@ ssize_t __file_read(struct file_info * fp, void *buf, size_t count)
 
     while (count) {
 	if (fp->i.nbytes == 0) {
-	    if (fp->i.offset >= fp->i.length || !fp->i.filedes)
+	    if (fp->i.offset >= fp->i.fd.size || !fp->i.fd.handle)
 		return n;	/* As good as it gets... */
 
 	    if (count > MAXBLOCK) {
 		/* Large transfer: copy directly, without buffering */
-		ncopy = __com32.cs_pm->read_file(&fp->i.filedes, bufp,
-						 count >> fp->i.blocklg2);
+		ncopy = __com32.cs_pm->read_file(&fp->i.fd.handle, bufp,
+						 count >> fp->i.fd.blocklg2);
 		if (!ncopy) {
 		    errno = EIO;
 		    return n ? n : -1;
diff --git a/com32/lib/sys/fstat.c b/com32/lib/sys/fstat.c
index 6a853933..0ce8cadb 100644
--- a/com32/lib/sys/fstat.c
+++ b/com32/lib/sys/fstat.c
@@ -45,14 +45,14 @@ int fstat(int fd, struct stat *buf)
     }
 
     if (fp->iop->flags & __DEV_FILE) {
-	if (fp->i.length == (uint32_t) - 1) {
+	if (fp->i.fd.size == (uint32_t) - 1) {
 	    /* File of unknown length, report it as a socket
 	       (it probably really is, anyway!) */
 	    buf->st_mode = S_IFSOCK | 0444;
 	    buf->st_size = 0;
 	} else {
 	    buf->st_mode = S_IFREG | 0444;
-	    buf->st_size = fp->i.length;
+	    buf->st_size = fp->i.fd.size;
 	}
     } else {
 	buf->st_mode = S_IFCHR | 0666;
diff --git a/com32/lib/sys/open.c b/com32/lib/sys/open.c
index 94465925..cb7c1b4d 100644
--- a/com32/lib/sys/open.c
+++ b/com32/lib/sys/open.c
@@ -52,10 +52,8 @@ const struct input_dev __file_dev = {
 
 int open(const char *pathname, int flags, ...)
 {
-    com32sys_t regs;
-    int fd;
+    int fd, handle;
     struct file_info *fp;
-    char *lm_pathname;
 
     fd = opendev(&__file_dev, NULL, flags);
 
@@ -64,31 +62,10 @@ int open(const char *pathname, int flags, ...)
 
     fp = &__file_info[fd];
 
-    lm_pathname = lstrdup(pathname);
-    if (!lm_pathname)
+    handle = __com32.cs_pm->open_file(pathname, &fp->i.fd);
+    if (handle < 0)
 	return -1;
 
-    regs.eax.w[0] = 0x0006;
-    regs.esi.w[0] = OFFS(lm_pathname);
-    regs.es = SEG(lm_pathname);
-
-    __com32.cs_intcall(0x22, &regs, &regs);
-
-    lfree(lm_pathname);
-
-    if ((regs.eflags.l & EFLAGS_CF) || regs.esi.w[0] == 0) {
-	close(fd);
-	errno = ENOENT;
-	return -1;
-    }
-
-    {
-	uint16_t blklg2;
-	asm("bsrw %1,%0" : "=r" (blklg2) : "rm" (regs.ecx.w[0]));
-	fp->i.blocklg2 = blklg2;
-    }
-    fp->i.length = regs.eax.l;
-    fp->i.filedes = regs.esi.w[0];
     fp->i.offset = 0;
     fp->i.nbytes = 0;
 
diff --git a/com32/lib/sys/openmem.c b/com32/lib/sys/openmem.c
index 33b8de0d..a56a4af8 100644
--- a/com32/lib/sys/openmem.c
+++ b/com32/lib/sys/openmem.c
@@ -52,9 +52,9 @@ int openmem(const void *base, size_t len, int flags)
 
     fp = &__file_info[fd];
 
-    fp->i.length  = fp->i.nbytes = len;
+    fp->i.fd.size  = fp->i.nbytes = len;
     fp->i.datap   = (void *)base;
-    fp->i.filedes = 0;		/* No actual file */
+    fp->i.fd.handle = 0;		/* No actual file */
     fp->i.offset  = 0;
 
     return fd;
diff --git a/com32/lib/sys/zfile.c b/com32/lib/sys/zfile.c
index a1213a94..0e6ba916 100644
--- a/com32/lib/sys/zfile.c
+++ b/com32/lib/sys/zfile.c
@@ -75,7 +75,7 @@ static int gzip_file_init(struct file_info *fp)
     }
 
     fp->iop = &gzip_file_dev;
-    fp->i.length = -1;		/* Unknown */
+    fp->i.fd.size = -1;		/* Unknown */
 
     return 0;
 }
@@ -92,7 +92,7 @@ static ssize_t gzip_file_read(struct file_info *fp, void *ptr, size_t n)
 	zs->next_out = p;
 	zs->avail_out = n;
 
-	if (!zs->avail_in && fp->i.filedes) {
+	if (!zs->avail_in && fp->i.fd.handle) {
 	    if (__file_get_block(fp))
 		return nout ? nout : -1;
 
@@ -154,7 +154,9 @@ int zopen(const char *pathname, int flags, ...)
     if (__file_get_block(fp))
 	goto err;
 
-    if (fp->i.nbytes >= 14 && (uint8_t) fp->i.buf[0] == 037 && (uint8_t) fp->i.buf[1] == 0213 &&	/* gzip */
+    if (fp->i.nbytes >= 14 &&
+	(uint8_t) fp->i.buf[0] == 037 &&
+	(uint8_t) fp->i.buf[1] == 0213 &&	/* gzip */
 	fp->i.buf[2] == 8)	/* deflate */
 	rv = gzip_file_init(fp);
     else