cosmopolitan/libc/runtime/zipos.internal.h
Justine Tunney b01282e23e
Rewrite ZipOS
This reduces the virtual memory usage of Emacs for me by 30%. We now
have a simpler implementation that uses read(), rather mmap()ing the
whole executable.
2023-10-03 07:27:25 -07:00

70 lines
2.3 KiB
C

#ifndef COSMOPOLITAN_ZIPOS_H_
#define COSMOPOLITAN_ZIPOS_H_
#include "libc/thread/thread.h"
#if !(__ASSEMBLER__ + __LINKER__ + 0)
COSMOPOLITAN_C_START_
#define ZIPOS_PATH_MAX 1024
#define ZIPOS_SYNTHETIC_DIRECTORY -2
struct stat;
struct iovec;
struct Zipos;
struct ZiposUri {
uint32_t len;
char path[ZIPOS_PATH_MAX];
};
struct ZiposHandle {
struct ZiposHandle *next;
struct Zipos *zipos;
int64_t handle; /* original upstream open()'d handle */
uint64_t size; /* accessible bytes stored at data[] */
uint64_t mapsize; /* the full byte size of this struct */
uint64_t pos; /* the file position, relative start */
int cfile; /* byte offset into zipos->cdir ents */
uint8_t data[]; /* original file content or dir name */
};
struct Zipos {
_Atomic(unsigned) once;
int cnt; /* element count, accessible via `index` */
int cdirsize; /* number of bytes accessible via `cdir` */
uint64_t dev; /* remembers st_dev, of zipos image file */
int *index; /* points to cdirsize+cnt*4 mmap'd bytes */
uint8_t *cdir; /* points after index, in the above mmap */
const char *progpath;
struct ZiposHandle *freelist;
char *mapend;
size_t maptotal;
pthread_mutex_t lock;
};
int __zipos_close(int);
void __zipos_lock(void);
void __zipos_unlock(void);
void __zipos_free(struct ZiposHandle *);
struct Zipos *__zipos_get(void) pureconst;
size_t __zipos_normpath(char *, const char *, size_t);
int __zipos_find(struct Zipos *, struct ZiposUri *);
int __zipos_scan(struct Zipos *, struct ZiposUri *);
ssize_t __zipos_parseuri(const char *, struct ZiposUri *);
uint64_t __zipos_inode(struct Zipos *, int64_t, const void *, size_t);
int __zipos_open(struct ZiposUri *, int);
int __zipos_access(struct ZiposUri *, int);
int __zipos_stat(struct ZiposUri *, struct stat *);
int __zipos_fstat(struct ZiposHandle *, struct stat *);
int __zipos_stat_impl(struct Zipos *, int, struct stat *);
ssize_t __zipos_read(struct ZiposHandle *, const struct iovec *, size_t,
ssize_t);
int64_t __zipos_seek(struct ZiposHandle *, int64_t, unsigned);
int __zipos_fcntl(int, int, uintptr_t);
int __zipos_notat(int, const char *);
void *__zipos_mmap(void *, uint64_t, int32_t, int32_t, struct ZiposHandle *,
int64_t);
COSMOPOLITAN_C_END_
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
#endif /* COSMOPOLITAN_ZIPOS_H_ */