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file_read(user_data, buffer, *size)
file = user_data
*size = fread(buffer, 1, *size, file)
extract(file_name, outer_member, inner_action)
FILE *file = fopen(file_name, "rb")
outer_gzip = gzip_init(&file_read, file)
outer_ustar = ustar_init(outer_gzip)
ustar_seek(outer_ustar, outer_member)
inner_gzip = gzip_init(&ustar_read, outer_ustar)
inner_ustar = ustar_init(inner_gzip)
inner_action(inner_ustar)
read_control(inner_ustar)
unsigned char buffer[512]
size
ustar_seek(inner_ustar, "control")
while ((ret = ustar_read(inner_ustar, buffer, &size)) == OK)
fwrite(buffer, 1 size, stdout)
if ret == ERROR
return
list_members(inner_ustar)
ustar_member member
while ((ret = ustar_list(inner_ustar, &member)) == OK)
printf("%s", member.name)
if ret == ERROR
return
main()
if -I
extract(argv[1], "control.tar.gz", &read_control)
else if -c
extract(argv[1], "data.tar.gz", &list_members)
---
struct gzip *
gzip_init(int (*read)(void *, char *, size_t *), void *user_data)
int
gzip_read(struct gzip *gzip, void *record)
---
struct ustar *
ustar_init(struct gzip *gzip)
int
ustar_list(struct ustar *ustar, ustar_member *member)
int
ustar_seek(ustruct star *ustar, const char *member)
int
ustar_read(struct ustar *ustar, char *buffer, size_t *size)
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