3 int lar_read32( int fd, uint32_t *val )
7 if( read(fd, buffer, 4) < 4 )
8 LAR_DIE("Unexpected EOF while reading data");
11 *val = ntohl(*((uint32_t *) buffer));
16 int lar_read16( int fd, uint16_t *val )
20 if( read(fd, buffer, 2) < 2 )
21 LAR_DIE("Unexpected EOF while reading data");
24 *val = ntohs(*((uint16_t *) buffer));
29 lar_index * lar_get_index( lar_archive *ar )
34 lar_index *idx_map, *idx_ptr;
36 if( lseek(ar->fd, -(sizeof(idx_offset)), SEEK_END) == -1 )
37 LAR_DIE("Unable to seek to end of archive");
39 lar_read32(ar->fd, &idx_offset);
40 idx_length = ( ar->length - idx_offset - sizeof(idx_offset) );
42 if( lseek(ar->fd, idx_offset, SEEK_SET) == -1 )
43 LAR_DIE("Unable to seek to archive index");
48 for( i = 0; i < idx_length; \
49 i += (sizeof(lar_index) - sizeof(char))
51 idx_ptr = (lar_index *)malloc(sizeof(lar_index));
53 lar_read32(ar->fd, &idx_ptr->noffset);
54 lar_read32(ar->fd, &idx_ptr->nlength);
55 lar_read32(ar->fd, &idx_ptr->foffset);
56 lar_read32(ar->fd, &idx_ptr->flength);
57 lar_read16(ar->fd, &idx_ptr->type);
58 lar_read16(ar->fd, &idx_ptr->flags);
60 idx_ptr->next = idx_map;
67 uint32_t lar_get_filename( lar_archive *ar,
68 lar_index *idx_ptr, char *filename
70 if( idx_ptr->nlength >= LAR_FNAME_BUFFER )
71 LAR_DIE("Filename exceeds maximum allowed length");
73 if( lseek(ar->fd, idx_ptr->noffset, SEEK_SET) == -1 )
74 LAR_DIE("Unexpected EOF while seeking filename");
76 if( read(ar->fd, filename, idx_ptr->nlength) < idx_ptr->nlength )
77 LAR_DIE("Unexpected EOF while reading filename");
79 filename[idx_ptr->nlength] = 0;
81 return idx_ptr->nlength;
84 lar_member * lar_open_member( lar_archive *ar, const char *name )
86 lar_index *idx_ptr = ar->index;
88 char memberfile[LAR_FNAME_BUFFER];
90 size_t pgsz = getpagesize();
94 lar_get_filename(ar, idx_ptr, memberfile);
96 if( !strncmp(memberfile, name, idx_ptr->nlength) )
99 0, idx_ptr->flength + ( idx_ptr->foffset % pgsz ),
100 PROT_READ, MAP_PRIVATE, ar->fd,
101 idx_ptr->foffset - ( idx_ptr->foffset % pgsz )
104 if( memberdata == MAP_FAILED )
105 LAR_DIE("Failed to mmap() member data");
107 member = (lar_member *)malloc(sizeof(lar_member));
108 member->type = idx_ptr->type;
109 member->flags = idx_ptr->flags;
110 member->length = idx_ptr->flength;
111 member->data = &memberdata[idx_ptr->foffset % pgsz];
113 member->mmap = memberdata;
114 member->mlen = idx_ptr->flength + ( idx_ptr->foffset % pgsz );
119 idx_ptr = idx_ptr->next;
125 int lar_close_member( lar_member *member )
127 int stat = munmap(member->mmap, member->mlen);
133 lar_archive * lar_open( const char *filename )
139 if( stat(filename, &as) == -1 )
142 if( !(as.st_mode & S_IFREG) )
145 if( (fd = open(filename, O_RDONLY)) != -1 )
147 ar = (lar_archive *)malloc(sizeof(lar_archive));
149 ar->length = as.st_size;
150 ar->index = lar_get_index(ar);
151 strncpy(ar->filename, filename, sizeof(ar->filename));
159 int lar_close( lar_archive *ar )
166 idx_head = ar->index;
168 idx_next = idx_head->next;
170 } while( (idx_head = idx_next) != NULL );