Changeset ed903174 in mainline for uspace/app/taskdump/elf_core.c

Timestamp:

2010-02-10T23:51:23Z (14 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

e70edd1

Parents:

b32c604f

Message:

implement support for 64bit file offsets

• the libc API is a small deviation from standard, but we have no reason to keep a strict backward compatibility with ancient code so far
  • the basic signed 64bit offset type is called off64_t
    • lseek() and fseek() take off64_t arguments (since the argument represents a relative offset)
    • ftell() returns off64_t values (since it is a wrapper of lseek())
    • vfs_seek() implementation supports negative offsets when SEEK_CUR and SEEK_END is used
  • aoff64_t is used for internal unsigned representation of sizes (in bytes, blocks, etc.) and absolute offsets
    • mmap() and ftruncate() take aoff64_t arguments (since the full range of the absolute file offset should be used here)
    • struct stat stores the file size as aoff64_t
  • in both cases the explicit range of the types shown in the names is helpful for proper filesystem and IPC interaction
  • note: size_t should be used only for representing in-memory sizes and offsets, not device and file-related information, and vice versa
    • the code base still needs a thorough revision with respect to this rule
  • PRIdOFF64 and PRIuOFF64 can be used for printing the offsets
• VFS_OUT_LOOKUP returns the 64bit file size in two IPC arguments
  • since all 5 IPC arguments have already been taken, the fs_handle is returned as the return value (fs_handle has only 16 bits, thus the return value can be used for both indicating errors as negative values and returning positive handles)
• VFS_OUT_READ and VFS_OUT_WRITE use aoff64_t absolute offsets split into two IPC arguments

replace bn_t with aoff64_t as a generic 64bit bytes/block counter type

note: filesystem drivers need to be revised with respect to make sure that all out-of-range checks are correct (especially w.r.t. file and block offsets)

File:

• uspace/app/taskdump/elf_core.c (modified) (5 diffs)

uspace/app/taskdump/elf_core.c

@@ -62 +62 @@
 #include "include/elf_core.h"
 
-static off_t align_foff_up(off_t foff, uintptr_t vaddr, size_t page_size);
+static off64_t align_foff_up(off64_t foff, uintptr_t vaddr, size_t page_size);
 static int write_all(int fd, void *data, size_t len);
 static int write_mem_area(int fd, as_area_info_t *area, int phoneid);
@@ -79 +79 @@
  *                      ENOMEM on out of memory, EIO on write error.
  */
-int elf_core_save(const char *file_name, as_area_info_t *ainfo, int n, int phoneid)
+int elf_core_save(const char *file_name, as_area_info_t *ainfo, unsigned int n, int phoneid)
 {
         elf_header_t elf_hdr;
-        off_t foff;
+        off64_t foff;
         size_t n_ph;
         elf_word flags;
@@ -89 +89 @@
         int fd;
         int rc;
-        int i;
+        unsigned int i;
 
         n_ph = n;
@@ -184 +184 @@
 
         for (i = 0; i < n_ph; ++i) {
-                if (lseek(fd, p_hdr[i].p_offset, SEEK_SET) == (off_t) -1) {
+                if (lseek(fd, p_hdr[i].p_offset, SEEK_SET) == (off64_t) -1) {
                         printf("Failed writing memory data.\n");
                         free(p_hdr);
@@ -202 +202 @@
 
 /** Align file offset up to be congruent with vaddr modulo page size. */
-static off_t align_foff_up(off_t foff, uintptr_t vaddr, size_t page_size)
-{
-        off_t rfo, rva;
-        off_t advance;
-
-        rva = vaddr % page_size;
-        rfo = foff % page_size;
-
-        advance = (rva >= rfo) ? rva - rfo : (page_size + rva - rfo);
-        return foff + advance;
+static off64_t align_foff_up(off64_t foff, uintptr_t vaddr, size_t page_size)
+{
+        off64_t rva = vaddr % page_size;
+        off64_t rfo = foff % page_size;
+        
+        if (rva >= rfo)
+                return (foff + (rva - rfo));
+        
+        return (foff + (page_size + (rva - rfo)));
 }