Merge pull request #536 from gameblabla/cdrom_fixes

[pcsx_rearmed.git] / deps / libchdr / src / libchdr_chd.c

diff --git a/deps/libchdr/src/libchdr_chd.c b/deps/libchdr/src/libchdr_chd.c
index 913abaa..c5cc179 100644 (file)
--- a/deps/libchdr/src/libchdr_chd.c
+++ b/deps/libchdr/src/libchdr_chd.c
@@ -1382,8 +1382,15 @@ CHD_EXPORT chd_error chd_open_file(core_file *file, int mode, chd_file *parent,
                EARLY_EXIT(err = CHDERR_UNSUPPORTED_VERSION);
 
        /* if we need a parent, make sure we have one */
-       if (parent == NULL && (newchd->header.flags & CHDFLAGS_HAS_PARENT))
-               EARLY_EXIT(err = CHDERR_REQUIRES_PARENT);
+       if (parent == NULL)
+       {
+               /* Detect parent requirement for versions below 5 */
+               if (newchd->header.version < 5 && newchd->header.flags & CHDFLAGS_HAS_PARENT)
+                       EARLY_EXIT(err = CHDERR_REQUIRES_PARENT);
+               /* Detection for version 5 and above - if parentsha1 != 0, we have a parent */
+               else if (newchd->header.version >= 5 && memcmp(nullsha1, newchd->header.parentsha1, sizeof(newchd->header.parentsha1)) != 0)
+                       EARLY_EXIT(err = CHDERR_REQUIRES_PARENT);
+       }
 
        /* make sure we have a valid parent */
        if (parent != NULL)
@@ -1676,6 +1683,9 @@ CHD_EXPORT void chd_close(chd_file *chd)
        if (chd->file_cache)
                free(chd->file_cache);
 
+       if (chd->parent)
+               chd_close(chd->parent);
+
        /* free our memory */
        free(chd);
 }
@@ -1749,6 +1759,41 @@ CHD_EXPORT const chd_header *chd_get_header(chd_file *chd)
        return &chd->header;
 }
 
+/*-------------------------------------------------
+    chd_read_header - read CHD header data
+       from file into the pointed struct
+-------------------------------------------------*/
+CHD_EXPORT chd_error chd_read_header(const char *filename, chd_header *header)
+{
+       chd_error err = CHDERR_NONE;
+       chd_file chd;
+
+       /* punt if NULL */
+       if (filename == NULL || header == NULL)
+               EARLY_EXIT(err = CHDERR_INVALID_PARAMETER);
+
+       /* open the file */
+       chd.file = core_fopen(filename);
+       if (chd.file == NULL)
+               EARLY_EXIT(err = CHDERR_FILE_NOT_FOUND);
+
+       /* attempt to read the header */
+       err = header_read(&chd, header);
+       if (err != CHDERR_NONE)
+               EARLY_EXIT(err);
+
+       /* validate the header */
+       err = header_validate(header);
+       if (err != CHDERR_NONE)
+               EARLY_EXIT(err);
+
+cleanup:
+       if (chd.file != NULL)
+               core_fclose(chd.file);
+
+       return err;
+}
+
 /***************************************************************************
     CORE DATA READ/WRITE
 ***************************************************************************/
@@ -2343,13 +2388,33 @@ static chd_error hunk_read_into_memory(chd_file *chd, UINT32 hunknum, UINT8 *des
                                return hunk_read_into_memory(chd, blockoffs, dest);
 
                        case COMPRESSION_PARENT:
-#if 0
-                               /* TODO */
-                               if (m_parent_missing)
+                               if (chd->parent == NULL)
                                        return CHDERR_REQUIRES_PARENT;
-                               return m_parent->read_bytes(uint64_t(blockoffs) * uint64_t(m_parent->unit_bytes()), dest, m_hunkbytes);
-#endif
-                               return CHDERR_DECOMPRESSION_ERROR;
+                               UINT8 units_in_hunk = chd->header.hunkbytes / chd->header.unitbytes;
+
+                               /* blockoffs is aligned to units_in_hunk */
+                               if (blockoffs % units_in_hunk == 0) {
+                                       return hunk_read_into_memory(chd->parent, blockoffs / units_in_hunk, dest);
+                               /* blockoffs is not aligned to units_in_hunk */
+                               } else {
+                                       UINT32 unit_in_hunk = blockoffs % units_in_hunk;
+                                       UINT8 *buf = malloc(chd->header.hunkbytes);
+                                       /* Read first half of hunk which contains blockoffs */
+                                       err = hunk_read_into_memory(chd->parent, blockoffs / units_in_hunk, buf);
+                                       if (err != CHDERR_NONE) {
+                                               free(buf);
+                                               return err;
+                                       }
+                                       memcpy(dest, buf + unit_in_hunk * chd->header.unitbytes, (units_in_hunk - unit_in_hunk) * chd->header.unitbytes);
+                                       /* Read second half of hunk which contains blockoffs */
+                                       err = hunk_read_into_memory(chd->parent, (blockoffs / units_in_hunk) + 1, buf);
+                                       if (err != CHDERR_NONE) {
+                                               free(buf);
+                                               return err;
+                                       }
+                                       memcpy(dest + (units_in_hunk - unit_in_hunk) * chd->header.unitbytes, buf, unit_in_hunk * chd->header.unitbytes);
+                                       free(buf);
+                               }
                }
                return CHDERR_NONE;
        }