| 1 | /* 7zStream.c -- 7z Stream functions\r |
| 2 | 2013-11-12 : Igor Pavlov : Public domain */\r |
| 3 | \r |
| 4 | #include "Precomp.h"\r |
| 5 | \r |
| 6 | #include <string.h>\r |
| 7 | \r |
| 8 | #include "7zTypes.h"\r |
| 9 | \r |
| 10 | SRes SeqInStream_Read2(ISeqInStream *stream, void *buf, size_t size, SRes errorType)\r |
| 11 | {\r |
| 12 | while (size != 0)\r |
| 13 | {\r |
| 14 | size_t processed = size;\r |
| 15 | RINOK(stream->Read(stream, buf, &processed));\r |
| 16 | if (processed == 0)\r |
| 17 | return errorType;\r |
| 18 | buf = (void *)((Byte *)buf + processed);\r |
| 19 | size -= processed;\r |
| 20 | }\r |
| 21 | return SZ_OK;\r |
| 22 | }\r |
| 23 | \r |
| 24 | SRes SeqInStream_Read(ISeqInStream *stream, void *buf, size_t size)\r |
| 25 | {\r |
| 26 | return SeqInStream_Read2(stream, buf, size, SZ_ERROR_INPUT_EOF);\r |
| 27 | }\r |
| 28 | \r |
| 29 | SRes SeqInStream_ReadByte(ISeqInStream *stream, Byte *buf)\r |
| 30 | {\r |
| 31 | size_t processed = 1;\r |
| 32 | RINOK(stream->Read(stream, buf, &processed));\r |
| 33 | return (processed == 1) ? SZ_OK : SZ_ERROR_INPUT_EOF;\r |
| 34 | }\r |
| 35 | \r |
| 36 | SRes LookInStream_SeekTo(ILookInStream *stream, UInt64 offset)\r |
| 37 | {\r |
| 38 | Int64 t = offset;\r |
| 39 | return stream->Seek(stream, &t, SZ_SEEK_SET);\r |
| 40 | }\r |
| 41 | \r |
| 42 | SRes LookInStream_LookRead(ILookInStream *stream, void *buf, size_t *size)\r |
| 43 | {\r |
| 44 | const void *lookBuf;\r |
| 45 | if (*size == 0)\r |
| 46 | return SZ_OK;\r |
| 47 | RINOK(stream->Look(stream, &lookBuf, size));\r |
| 48 | memcpy(buf, lookBuf, *size);\r |
| 49 | return stream->Skip(stream, *size);\r |
| 50 | }\r |
| 51 | \r |
| 52 | SRes LookInStream_Read2(ILookInStream *stream, void *buf, size_t size, SRes errorType)\r |
| 53 | {\r |
| 54 | while (size != 0)\r |
| 55 | {\r |
| 56 | size_t processed = size;\r |
| 57 | RINOK(stream->Read(stream, buf, &processed));\r |
| 58 | if (processed == 0)\r |
| 59 | return errorType;\r |
| 60 | buf = (void *)((Byte *)buf + processed);\r |
| 61 | size -= processed;\r |
| 62 | }\r |
| 63 | return SZ_OK;\r |
| 64 | }\r |
| 65 | \r |
| 66 | SRes LookInStream_Read(ILookInStream *stream, void *buf, size_t size)\r |
| 67 | {\r |
| 68 | return LookInStream_Read2(stream, buf, size, SZ_ERROR_INPUT_EOF);\r |
| 69 | }\r |
| 70 | \r |
| 71 | static SRes LookToRead_Look_Lookahead(void *pp, const void **buf, size_t *size)\r |
| 72 | {\r |
| 73 | SRes res = SZ_OK;\r |
| 74 | CLookToRead *p = (CLookToRead *)pp;\r |
| 75 | size_t size2 = p->size - p->pos;\r |
| 76 | if (size2 == 0 && *size > 0)\r |
| 77 | {\r |
| 78 | p->pos = 0;\r |
| 79 | size2 = LookToRead_BUF_SIZE;\r |
| 80 | res = p->realStream->Read(p->realStream, p->buf, &size2);\r |
| 81 | p->size = size2;\r |
| 82 | }\r |
| 83 | if (size2 < *size)\r |
| 84 | *size = size2;\r |
| 85 | *buf = p->buf + p->pos;\r |
| 86 | return res;\r |
| 87 | }\r |
| 88 | \r |
| 89 | static SRes LookToRead_Look_Exact(void *pp, const void **buf, size_t *size)\r |
| 90 | {\r |
| 91 | SRes res = SZ_OK;\r |
| 92 | CLookToRead *p = (CLookToRead *)pp;\r |
| 93 | size_t size2 = p->size - p->pos;\r |
| 94 | if (size2 == 0 && *size > 0)\r |
| 95 | {\r |
| 96 | p->pos = 0;\r |
| 97 | if (*size > LookToRead_BUF_SIZE)\r |
| 98 | *size = LookToRead_BUF_SIZE;\r |
| 99 | res = p->realStream->Read(p->realStream, p->buf, size);\r |
| 100 | size2 = p->size = *size;\r |
| 101 | }\r |
| 102 | if (size2 < *size)\r |
| 103 | *size = size2;\r |
| 104 | *buf = p->buf + p->pos;\r |
| 105 | return res;\r |
| 106 | }\r |
| 107 | \r |
| 108 | static SRes LookToRead_Skip(void *pp, size_t offset)\r |
| 109 | {\r |
| 110 | CLookToRead *p = (CLookToRead *)pp;\r |
| 111 | p->pos += offset;\r |
| 112 | return SZ_OK;\r |
| 113 | }\r |
| 114 | \r |
| 115 | static SRes LookToRead_Read(void *pp, void *buf, size_t *size)\r |
| 116 | {\r |
| 117 | CLookToRead *p = (CLookToRead *)pp;\r |
| 118 | size_t rem = p->size - p->pos;\r |
| 119 | if (rem == 0)\r |
| 120 | return p->realStream->Read(p->realStream, buf, size);\r |
| 121 | if (rem > *size)\r |
| 122 | rem = *size;\r |
| 123 | memcpy(buf, p->buf + p->pos, rem);\r |
| 124 | p->pos += rem;\r |
| 125 | *size = rem;\r |
| 126 | return SZ_OK;\r |
| 127 | }\r |
| 128 | \r |
| 129 | static SRes LookToRead_Seek(void *pp, Int64 *pos, ESzSeek origin)\r |
| 130 | {\r |
| 131 | CLookToRead *p = (CLookToRead *)pp;\r |
| 132 | p->pos = p->size = 0;\r |
| 133 | return p->realStream->Seek(p->realStream, pos, origin);\r |
| 134 | }\r |
| 135 | \r |
| 136 | void LookToRead_CreateVTable(CLookToRead *p, int lookahead)\r |
| 137 | {\r |
| 138 | p->s.Look = lookahead ?\r |
| 139 | LookToRead_Look_Lookahead :\r |
| 140 | LookToRead_Look_Exact;\r |
| 141 | p->s.Skip = LookToRead_Skip;\r |
| 142 | p->s.Read = LookToRead_Read;\r |
| 143 | p->s.Seek = LookToRead_Seek;\r |
| 144 | }\r |
| 145 | \r |
| 146 | void LookToRead_Init(CLookToRead *p)\r |
| 147 | {\r |
| 148 | p->pos = p->size = 0;\r |
| 149 | }\r |
| 150 | \r |
| 151 | static SRes SecToLook_Read(void *pp, void *buf, size_t *size)\r |
| 152 | {\r |
| 153 | CSecToLook *p = (CSecToLook *)pp;\r |
| 154 | return LookInStream_LookRead(p->realStream, buf, size);\r |
| 155 | }\r |
| 156 | \r |
| 157 | void SecToLook_CreateVTable(CSecToLook *p)\r |
| 158 | {\r |
| 159 | p->s.Read = SecToLook_Read;\r |
| 160 | }\r |
| 161 | \r |
| 162 | static SRes SecToRead_Read(void *pp, void *buf, size_t *size)\r |
| 163 | {\r |
| 164 | CSecToRead *p = (CSecToRead *)pp;\r |
| 165 | return p->realStream->Read(p->realStream, buf, size);\r |
| 166 | }\r |
| 167 | \r |
| 168 | void SecToRead_CreateVTable(CSecToRead *p)\r |
| 169 | {\r |
| 170 | p->s.Read = SecToRead_Read;\r |
| 171 | }\r |