commit eae10049d149360f755c91e4a8a9d965a8e7654f Author: Daniele Lacamera Date: Mon Oct 21 19:23:55 2019 +0200 Initial import diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..e58ea41 --- /dev/null +++ b/.gitignore @@ -0,0 +1,3 @@ +.o +test/test +tags diff --git a/COPYING b/COPYING new file mode 100644 index 0000000..d159169 --- /dev/null +++ b/COPYING @@ -0,0 +1,339 @@ + GNU GENERAL PUBLIC LICENSE + Version 2, June 1991 + + Copyright (C) 1989, 1991 Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public +License is intended to guarantee your freedom to share and change free +software--to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. (Some other Free Software Foundation software is covered by +the GNU Lesser General Public License instead.) You can apply it to +your programs, too. + + When we speak of free software, we are referring to freedom, not +price. Our General Public Licenses are designed to make sure that you +have the freedom to distribute copies of free software (and charge for +this service if you wish), that you receive source code or can get it +if you want it, that you can change the software or use pieces of it +in new free programs; and that you know you can do these things. + + To protect your rights, we need to make restrictions that forbid +anyone to deny you these rights or to ask you to surrender the rights. +These restrictions translate to certain responsibilities for you if you +distribute copies of the software, or if you modify it. + + For example, if you distribute copies of such a program, whether +gratis or for a fee, you must give the recipients all the rights that +you have. You must make sure that they, too, receive or can get the +source code. And you must show them these terms so they know their +rights. + + We protect your rights with two steps: (1) copyright the software, and +(2) offer you this license which gives you legal permission to copy, +distribute and/or modify the software. + + Also, for each author's protection and ours, we want to make certain +that everyone understands that there is no warranty for this free +software. If the software is modified by someone else and passed on, we +want its recipients to know that what they have is not the original, so +that any problems introduced by others will not reflect on the original +authors' reputations. + + Finally, any free program is threatened constantly by software +patents. We wish to avoid the danger that redistributors of a free +program will individually obtain patent licenses, in effect making the +program proprietary. To prevent this, we have made it clear that any +patent must be licensed for everyone's free use or not licensed at all. + + The precise terms and conditions for copying, distribution and +modification follow. + + GNU GENERAL PUBLIC LICENSE + TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION + + 0. This License applies to any program or other work which contains +a notice placed by the copyright holder saying it may be distributed +under the terms of this General Public License. The "Program", below, +refers to any such program or work, and a "work based on the Program" +means either the Program or any derivative work under copyright law: +that is to say, a work containing the Program or a portion of it, +either verbatim or with modifications and/or translated into another +language. (Hereinafter, translation is included without limitation in +the term "modification".) Each licensee is addressed as "you". + +Activities other than copying, distribution and modification are not +covered by this License; they are outside its scope. The act of +running the Program is not restricted, and the output from the Program +is covered only if its contents constitute a work based on the +Program (independent of having been made by running the Program). +Whether that is true depends on what the Program does. + + 1. You may copy and distribute verbatim copies of the Program's +source code as you receive it, in any medium, provided that you +conspicuously and appropriately publish on each copy an appropriate +copyright notice and disclaimer of warranty; keep intact all the +notices that refer to this License and to the absence of any warranty; +and give any other recipients of the Program a copy of this License +along with the Program. + +You may charge a fee for the physical act of transferring a copy, and +you may at your option offer warranty protection in exchange for a fee. + + 2. You may modify your copy or copies of the Program or any portion +of it, thus forming a work based on the Program, and copy and +distribute such modifications or work under the terms of Section 1 +above, provided that you also meet all of these conditions: + + a) You must cause the modified files to carry prominent notices + stating that you changed the files and the date of any change. + + b) You must cause any work that you distribute or publish, that in + whole or in part contains or is derived from the Program or any + part thereof, to be licensed as a whole at no charge to all third + parties under the terms of this License. + + c) If the modified program normally reads commands interactively + when run, you must cause it, when started running for such + interactive use in the most ordinary way, to print or display an + announcement including an appropriate copyright notice and a + notice that there is no warranty (or else, saying that you provide + a warranty) and that users may redistribute the program under + these conditions, and telling the user how to view a copy of this + License. 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But when you +distribute the same sections as part of a whole which is a work based +on the Program, the distribution of the whole must be on the terms of +this License, whose permissions for other licensees extend to the +entire whole, and thus to each and every part regardless of who wrote it. + +Thus, it is not the intent of this section to claim rights or contest +your rights to work written entirely by you; rather, the intent is to +exercise the right to control the distribution of derivative or +collective works based on the Program. + +In addition, mere aggregation of another work not based on the Program +with the Program (or with a work based on the Program) on a volume of +a storage or distribution medium does not bring the other work under +the scope of this License. + + 3. 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Each time you redistribute the Program (or any work based on the +Program), the recipient automatically receives a license from the +original licensor to copy, distribute or modify the Program subject to +these terms and conditions. You may not impose any further +restrictions on the recipients' exercise of the rights granted herein. +You are not responsible for enforcing compliance by third parties to +this License. + + 7. If, as a consequence of a court judgment or allegation of patent +infringement or for any other reason (not limited to patent issues), +conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot +distribute so as to satisfy simultaneously your obligations under this +License and any other pertinent obligations, then as a consequence you +may not distribute the Program at all. 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The Free Software Foundation may publish revised and/or new versions +of the General Public License from time to time. Such new versions will +be similar in spirit to the present version, but may differ in detail to +address new problems or concerns. + +Each version is given a distinguishing version number. If the Program +specifies a version number of this License which applies to it and "any +later version", you have the option of following the terms and conditions +either of that version or of any later version published by the Free +Software Foundation. If the Program does not specify a version number of +this License, you may choose any version ever published by the Free Software +Foundation. + + 10. If you wish to incorporate parts of the Program into other free +programs whose distribution conditions are different, write to the author +to ask for permission. For software which is copyrighted by the Free +Software Foundation, write to the Free Software Foundation; we sometimes +make exceptions for this. Our decision will be guided by the two goals +of preserving the free status of all derivatives of our free software and +of promoting the sharing and reuse of software generally. + + NO WARRANTY + + 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY +FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN +OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES +PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED +OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS +TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE +PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, +REPAIR OR CORRECTION. + + 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR +REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, +INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING +OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED +TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY +YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER +PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE +POSSIBILITY OF SUCH DAMAGES. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +convey the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + +Also add information on how to contact you by electronic and paper mail. + +If the program is interactive, make it output a short notice like this +when it starts in an interactive mode: + + Gnomovision version 69, Copyright (C) year name of author + Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, the commands you use may +be called something other than `show w' and `show c'; they could even be +mouse-clicks or menu items--whatever suits your program. + +You should also get your employer (if you work as a programmer) or your +school, if any, to sign a "copyright disclaimer" for the program, if +necessary. Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the program + `Gnomovision' (which makes passes at compilers) written by James Hacker. + + , 1 April 1989 + Ty Coon, President of Vice + +This General Public License does not permit incorporating your program into +proprietary programs. If your program is a subroutine library, you may +consider it more useful to permit linking proprietary applications with the +library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. diff --git a/src/usecfs.c b/src/usecfs.c new file mode 100644 index 0000000..3145ee7 --- /dev/null +++ b/src/usecfs.c @@ -0,0 +1,427 @@ +#include +#include +#include "usecfs.h" +#include "usecfs_dev.h" + +#ifndef NULL +# define NULL (void *)0 +#endif + +#define NO_BLOCK (0xFFFFFFFFUL) +#ifndef BLOCKDEV_OPEN_ARGS +# define BLOCKDEV_OPEN_ARGS (NULL) +#endif + +#define MAX_BLOCKS_0 ((BLOCK_SIZE - MAX_FILENAME) / 4) - 3 /* accounts for 3 32B fields + FILENAME */ +#define MAX_BLOCKS_N ((BLOCK_SIZE - MAX_FILENAME) / 4) - 1 /* overhead is only 'extra' fields */ +#define MAX_INLINE_SIZE ((MAX_BLOCKS_0 - 1) * 4) /* Max data size for self-contained block */ +#define INLINE_PAYLOAD(x) ((uint8_t *)(&x->blk[1])) /* Macro to access INLINE paylaod */ + +static uint8_t cache[BLOCK_SIZE]; +static uint8_t inline_buffer_copy[MAX_INLINE_SIZE]; + +struct __attribute__((packed)) extra { + uint32_t extra; + uint32_t blk[(BLOCK_SIZE / 4) - 1]; +}; + +struct __attribute__((packed)) inode { + uint32_t extra; + uint32_t blk[((BLOCK_SIZE - MAX_FILENAME) / 4) - 3]; + uint32_t size; + uint32_t nextfile; + char filename[MAX_FILENAME]; +}; + +/* One-sector cache, single entry point for read/write + * on blocks + */ + +static uint32_t cached_block = NO_BLOCK; +void *blockdev = NULL; +static void cache_commit(void) +{ + if (cached_block == NO_BLOCK) + return; + block_write(blockdev, cache, cached_block, 0, BLOCK_SIZE); + cached_block = NO_BLOCK; +} + +static void cache_load(uint32_t blk) +{ + if (cached_block == blk) + return; + if (cached_block != NO_BLOCK) + cache_commit(); + if (block_read(blockdev, cache, blk, 0, BLOCK_SIZE) == BLOCK_SIZE) + cached_block = blk; +} + + + +static uint32_t get_file(const char *filename) +{ + struct inode *ci = (struct inode *)cache; + uint32_t blk = 0; + cache_load(blk); + while (1) { + if (strncmp(filename, ci->filename, MAX_FILENAME - 1) == 0) + return blk; + if (ci->nextfile != NO_BLOCK) { + blk = ci->nextfile; + cache_load(blk); + } else + return NO_BLOCK; + } + return NO_BLOCK; /* Never reached */ +} + +static uint32_t get_free_block(uint32_t *fs_tail) +{ + struct inode *ci = (struct inode *)cache; + struct extra *ce = (struct extra *)cache; + uint32_t first_free = 1; + uint32_t cur_inode_0 = 0; + int i; + cache_load(0); + while (1) { + for (i = 0; i < MAX_BLOCKS_0; i++) + { + if (ci->blk[i] == NO_BLOCK) + break; + if (first_free == ci->blk[i]) + first_free++; + } + if (ci->extra != NO_BLOCK) + { + cache_load(ci->extra); + while (1) { + for (i = 0; i < MAX_BLOCKS_N; i++) + { + if (ce->blk[i] == NO_BLOCK) + break; + if (first_free == ce->blk[i]) + first_free++; + } + if (ce->extra == NO_BLOCK) + break; + cache_load(ce->extra); + } + cache_load(cur_inode_0); + } + if (ci->nextfile != NO_BLOCK) { + cur_inode_0 = ci->nextfile; + cache_load(cur_inode_0); + } else { + if (fs_tail) + *fs_tail = cur_inode_0; + return first_free; + } + } +} + +static uint32_t new_inode(void) +{ + struct inode *ci = (struct inode *)cache; + uint32_t fs_tail = NO_BLOCK; + uint32_t new_block = get_free_block(&fs_tail); + if (new_block == NO_BLOCK || fs_tail == NO_BLOCK) + return NO_BLOCK; + + cache_load(fs_tail); + ci->nextfile = new_block; + cache_load(new_block); + ci->nextfile = NO_BLOCK; + return new_block; +} + +struct openfile { + uint32_t blk; + uint32_t off; +}; +struct openfile OpenFiles[MAX_OPEN_FILES]; + +static int get_free_fd(void) +{ + int i, free_fd = -1; + + for (i = 0; i < MAX_OPEN_FILES; i++) { + if (OpenFiles[i].blk == NO_BLOCK) { + free_fd = i; + break; + } + } + return free_fd; +} + +int usecfs_open(const char *name) +{ + int free_fd; + free_fd = get_free_fd(); + if (free_fd < 0) + return -1; + OpenFiles[free_fd].blk = get_file(name); + if (OpenFiles[free_fd].blk == NO_BLOCK) + return -1; + OpenFiles[free_fd].off = 0; + return free_fd; +} + +int usecfs_creat(const char *name) +{ + int free_fd; + int i; + uint32_t newnode; + struct inode *ci = (struct inode *)cache; + free_fd = get_free_fd(); + if (free_fd < 0) + return -1; + if (get_file(name) != NO_BLOCK) + return -1; + newnode = new_inode(); + if (newnode == NO_BLOCK) + return -1; + OpenFiles[free_fd].blk = newnode; + + /* Initialize inode (already in cache from new_inode()) */ + ci->size = 0; /* newly created file is zero bytes long */ + memset(ci->filename, 0, MAX_FILENAME); + for (i = 0; (i < strlen(name)) && (i < MAX_FILENAME - 1); i++) + ci->filename[i] = name[i]; + ci->blk[0] = newnode; /* self-reference, start as INLINE */ + for (i = 1; i < MAX_BLOCKS_0; i++) + ci->blk[i] = NO_BLOCK; + OpenFiles[free_fd].off = 0; + cache_commit(); + return free_fd; +} + +static uint32_t get_index_block(uint32_t inode0, uint32_t off) +{ + struct inode *ci = (struct inode *)cache; + struct extra *ce = (struct extra *)cache; + uint32_t idx = 0; + cache_load(inode0); + idx = off / BLOCK_SIZE; + if (idx <= MAX_BLOCKS_0) + return inode0; + if (ci->extra == NO_BLOCK) + return NO_BLOCK; + inode0 = ci->extra; + cache_load(inode0); + idx -= MAX_BLOCKS_0; + while (idx >= MAX_BLOCKS_N) { + if (ce->extra == NO_BLOCK) + return NO_BLOCK; + inode0 = ce->extra; + cache_load(inode0); + idx -= MAX_BLOCKS_N; + } + return inode0; +} + +static void set_block(uint32_t node0, uint32_t nodeN, uint32_t off) +{ + struct inode *ci = (struct inode *)cache; + struct extra *ce = (struct extra *)cache; + uint32_t idx; + uint32_t idxblk; + idxblk = get_index_block(node0, off); +} + +static void file_grow(uint32_t node0, uint32_t newsize) +{ + struct inode *ci = (struct inode *)cache; + struct extra *ce = (struct extra *)cache; + uint32_t cur_idx, new_idx; + uint32_t cur_idx_block, new_idx_block; + uint32_t i; + cache_load(node0); + cur_idx = ci->size / BLOCK_SIZE; + new_idx = newsize / BLOCK_SIZE; + cur_idx_block = get_index_block(node0, ci->size); + new_idx_block = get_index_block(node0, newsize); + + for (i = cur_idx; i < new_idx; i++) { + cur_idx_block = get_index_block(node0, i * BLOCK_SIZE); + if (cur_idx_block == NO_BLOCK) + return; + cache_load(cur_idx_block); + if (cur_idx_block == node0) { + uint32_t idx = i + 1; + if (idx == (MAX_BLOCKS_0)) { + uint32_t extra = get_free_block(NULL); + cache_load(extra); + memset(cache, 0xFF, BLOCK_SIZE); + cache_load(node0); + ci->extra = extra; + cache_load(extra); + idx = 0; + } + ci->blk[idx] = get_free_block(NULL); + } else { + uint32_t idx = ((i - MAX_BLOCKS_0) % MAX_BLOCKS_N) + 1; + if (idx == MAX_BLOCKS_N) { + uint32_t extra = get_free_block(NULL); + cache_load(extra); + memset(cache, 0xFF, BLOCK_SIZE); + cache_load(cur_idx_block); + ce->extra = extra; + cache_load(extra); + idx = 0; + } + ce->blk[idx] = get_free_block(NULL); + } + } + if (ci->size < newsize) + ci->size = newsize; +} + +int usecfs_read(int fd, void *data, uint32_t len) +{ + int r = 0; + uint32_t node0 = OpenFiles[fd].blk; + uint32_t *off = &OpenFiles[fd].off; + struct inode *ci = (struct inode *)cache; + if (node0 == NO_BLOCK) + return -1; + cache_load(node0); + if ((ci->size - *off) < len) + len = ci->size - *off; + if (ci->blk[0] == node0) { + /* file is INLINE */ + memcpy(data, INLINE_PAYLOAD(ci), len); + *off += len; + return len; + } + while (r < len) { + int idx = *off / BLOCK_SIZE; + uint32_t idx_block; + uint32_t off_within_block; + uint32_t len_within_block; + + /* Find the index block for the offset */ + idx_block = get_index_block(node0, *off); + if (idx_block == NO_BLOCK) + return -1; + cache_load(idx_block); + if (ci->blk[idx] == NO_BLOCK) + return -1; + cache_load(ci->blk[idx]); + + /* Find the offset/len within this block */ + off_within_block = *off % BLOCK_SIZE; + len_within_block = BLOCK_SIZE - off_within_block; + if (len_within_block > (len - r)) + len_within_block = (len - r); + + /* Copy data from cache, increase counters */ + memcpy(data + r, cache + off_within_block, len_within_block); + r += len_within_block; + *off += len_within_block; + } + return len; +} + +int usecfs_write(int fd, const void *data, uint32_t len) +{ + int w = 0; + uint32_t node0 = OpenFiles[fd].blk; + uint32_t *off = &OpenFiles[fd].off; + struct inode *ci = (struct inode *)cache; + uint32_t blkn; + if (node0 == NO_BLOCK) + return -1; + cache_load(node0); + if (ci->size + *off <= MAX_INLINE_SIZE) { + if (ci->size + *off + len <= MAX_INLINE_SIZE) { + /* file can still be inline */ + memcpy(INLINE_PAYLOAD(ci) + *off, data, len); + *off += len; + if (*off > ci->size) + ci->size = *off; + cache_commit(); + return len; + } else { + /* Special case: migrating data to new block */ + memcpy(inline_buffer_copy, INLINE_PAYLOAD(ci), MAX_INLINE_SIZE); + blkn = get_free_block(NULL); + memcpy(cache, inline_buffer_copy, MAX_INLINE_SIZE); + cache_load(node0); + ci->blk[0] = blkn; + } + } + if (ci->size < *off + len) + file_grow(node0, *off + len); + + while (w < len) { + uint32_t off_within_block; + uint32_t len_within_block; + int idx = *off / BLOCK_SIZE; + uint32_t idx_block; + + idx_block = get_index_block(node0, *off); + if (idx_block == NO_BLOCK) + return -1; + + cache_load(idx_block); + off_within_block = *off % BLOCK_SIZE; + len_within_block = BLOCK_SIZE - off_within_block; + if (len_within_block > (len - w)) + len_within_block = (len - w); + if (ci->blk[idx] == NO_BLOCK) + return -1; + cache_load(ci->blk[idx]); + memcpy(cache + off_within_block, data + w, len_within_block); + w += len_within_block; + *off += len_within_block; + } + return len; +} + +int usecfs_seek(int fd, int offset, int whence) +{ + struct inode *ci = (struct inode *)cache; + if (OpenFiles[fd].blk == NO_BLOCK) + return -1; + cache_load(OpenFiles[fd].blk); + switch(whence) { + case 0: /* SEEK_SET */ + if (offset < 0) + return -1; + OpenFiles[fd].off = offset; + break; + case 1: /* SEEK_CUR */ + if ((OpenFiles[fd].off - offset) < 0) + OpenFiles[fd].off = 0; + else + OpenFiles[fd].off += offset; + break; + case 2: /* SEEK_END */ + OpenFiles[fd].off = ci->size + offset; + break; + default: + return -1; + } /* switch(whence) */ + if (OpenFiles[fd].off > ci->size) + file_grow(OpenFiles[fd].blk, OpenFiles[fd].off); + return OpenFiles[fd].off; +} + + +int usecfs_close(int fd) +{ + if (OpenFiles[fd].blk != NO_BLOCK) { + cache_commit(); + OpenFiles[fd].blk = NO_BLOCK; + } +} + +int usecfs_init(void) +{ + blockdev = block_open(BLOCKDEV_OPEN_ARGS); + if (!blockdev) + return -1; + memset(OpenFiles, 0xFF, MAX_OPEN_FILES * sizeof(struct openfile)); + return 0; +} diff --git a/src/usecfs.h b/src/usecfs.h new file mode 100644 index 0000000..26b3c91 --- /dev/null +++ b/src/usecfs.h @@ -0,0 +1,15 @@ +#ifndef INC_USECFS +#define INC_USECFS +#define MAX_FILENAME 256 +#define MAX_OPEN_FILES 16 +#include + +int usecfs_init(void); +int usecfs_open(const char *name); +int usecfs_creat(const char *name); +int usecfs_read(int fd, void *data, uint32_t len); +int usecfs_write(int fd, const void *data, uint32_t len); +int usecfs_seek(int fd, int offset, int whence); +int usecfs_close(int fd); + +#endif diff --git a/src/usecfs_dev.h b/src/usecfs_dev.h new file mode 100644 index 0000000..7a35f14 --- /dev/null +++ b/src/usecfs_dev.h @@ -0,0 +1,13 @@ +#ifndef INC_USECFS_BLOCK +#define INC_USECFS_BLOCK + +#ifndef BLOCK_SIZE +# define BLOCK_SIZE 512 +#endif + +void *block_open(void *args); +int block_read(void *dev, void *_buf, uint32_t lba, int offset, int count); +int block_write(void *dev, const void *_buf, uint32_t lba, int offset, int count); +void block_close(void *dev); + +#endif diff --git a/src/usecfs_dev_test.c b/src/usecfs_dev_test.c new file mode 100644 index 0000000..0696555 --- /dev/null +++ b/src/usecfs_dev_test.c @@ -0,0 +1,41 @@ +#include +#include +#include +#include +#include "usecfs_dev.h" + +static int fd = -1; + +#define FS_SIZE 1024 * 1024 +void *block_open(void *args) +{ + char *file = (char *)args; + int i; + uint8_t ff = 0xFF; + fd = open(file, O_RDWR | O_CREAT | O_TRUNC, 0660); + if (fd < 0) + return NULL; + for (i = 0; i < FS_SIZE; i++) + write(fd, &ff, 1); + lseek(fd, 0, SEEK_SET); + return &fd; +} + +int block_read(void *dev, void *_buf, uint32_t lba, int offset, int count) +{ + (void)dev; + lseek(fd, lba * BLOCK_SIZE + offset, SEEK_SET); + read(fd, _buf, count); +} + +int block_write(void *dev, const void *_buf, uint32_t lba, int offset, int count) +{ + (void)dev; + lseek(fd, lba * BLOCK_SIZE + offset, SEEK_SET); + write(fd, _buf, count); +} +void block_close(void *dev) +{ + (void)dev; + close(fd); +} diff --git a/test/Makefile b/test/Makefile new file mode 100644 index 0000000..f8ae3e2 --- /dev/null +++ b/test/Makefile @@ -0,0 +1,9 @@ +CFLAGS:=-I../src/ -DBLOCKDEV_OPEN_ARGS=\"test.bin\" -g -ggdb + +all: test + +test: main.o ../src/usecfs.o ../src/usecfs_dev_test.o + gcc -o $@ $^ + +clean: + rm main.o ../src/usecfs.o ../src/usecfs_dev_test.o test diff --git a/test/main.c b/test/main.c new file mode 100644 index 0000000..23eb551 --- /dev/null +++ b/test/main.c @@ -0,0 +1,46 @@ +#include "usecfs.h" +#include + + +int main(void) +{ + int fd; + int buf[36]; + + if (usecfs_init() < 0) + { + printf("error.\n"); + return 1; + } + + fd = usecfs_creat("file1"); + if (fd < 0) { + printf("error: creat.\n"); + return 1; + } + + if (usecfs_write(fd, "test string file 1 content", 26) < 0) { + printf("error: write.\n"); + return 1; + } + usecfs_close(fd); + + fd = usecfs_open("file1"); + if (fd < 0) { + printf("error: open\n"); + return 1; + } + if (usecfs_read(fd, buf, 26) != 26) { + printf("error: read.\n"); + return 1; + } + if (usecfs_write(fd, "test string2", 12) < 0) { + printf("error: write.\n"); + return 1; + } + if (usecfs_seek(fd, 0, 0) != 0) { + printf("error: seek.\n"); + return 1; + } + return 0; +} diff --git a/test/test.bin b/test/test.bin new file mode 100644 index 0000000..1ff5695 Binary files /dev/null and b/test/test.bin differ