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GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavcodec/mlz.c	Lines:	0	125	0.0 %
Date:	2020-01-27 20:17:04	Branches:	0	59	0.0 %


/*
 * Copyright (c) 2016 Umair Khan <omerjerk@gmail.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "mlz.h"

av_cold void ff_mlz_init_dict(void* context, MLZ *mlz) {
    mlz->dict = av_mallocz_array(TABLE_SIZE, sizeof(*mlz->dict));

    mlz->flush_code            = FLUSH_CODE;
    mlz->current_dic_index_max = DIC_INDEX_INIT;
    mlz->dic_code_bit          = CODE_BIT_INIT;
    mlz->bump_code             = (DIC_INDEX_INIT - 1);
    mlz->next_code             = FIRST_CODE;
    mlz->freeze_flag           = 0;
    mlz->context               = context;
}

av_cold void ff_mlz_flush_dict(MLZ *mlz) {
    MLZDict *dict = mlz->dict;
    int i;
    for ( i = 0; i < TABLE_SIZE; i++ ) {
        dict[i].string_code = CODE_UNSET;
        dict[i].parent_code = CODE_UNSET;
        dict[i].match_len = 0;
    }
    mlz->current_dic_index_max = DIC_INDEX_INIT;
    mlz->dic_code_bit          = CODE_BIT_INIT;  // DicCodeBitInit;
    mlz->bump_code             = mlz->current_dic_index_max - 1;
    mlz->next_code             = FIRST_CODE;
    mlz->freeze_flag           = 0;
}

static void set_new_entry_dict(MLZDict* dict, int string_code, int parent_code, int char_code) {
    dict[string_code].parent_code = parent_code;
    dict[string_code].string_code = string_code;
    dict[string_code].char_code   = char_code;
    if (parent_code < FIRST_CODE) {
        dict[string_code].match_len = 2;
    } else {
        dict[string_code].match_len = (dict[parent_code].match_len) + 1;
    }
}

static int decode_string(MLZ* mlz, unsigned char *buff, int string_code, int *first_char_code, unsigned long bufsize) {
    MLZDict* dict = mlz->dict;
    unsigned long count, offset;
    int current_code, parent_code, tmp_code;

    count            = 0;
    current_code     = string_code;
    *first_char_code = CODE_UNSET;

    while (count < bufsize) {
        switch (current_code) {
        case CODE_UNSET:
            return count;
            break;
        default:
            if (current_code < FIRST_CODE) {
                *first_char_code = current_code;
                buff[0] = current_code;
                count++;
                return count;
            } else {
                offset  = dict[current_code].match_len - 1;
                tmp_code = dict[current_code].char_code;
                if (offset >= bufsize) {
                    av_log(mlz->context, AV_LOG_ERROR, "MLZ offset error.\n");
                    return count;
                }
                buff[offset] = tmp_code;
                count++;
            }
            current_code = dict[current_code].parent_code;
            if ((current_code < 0) || (current_code > (DIC_INDEX_MAX - 1))) {
                av_log(mlz->context, AV_LOG_ERROR, "MLZ dic index error.\n");
                return count;
            }
            if (current_code > FIRST_CODE) {
                parent_code = dict[current_code].parent_code;
                offset = (dict[current_code].match_len) - 1;
                if (parent_code < 0 || parent_code > DIC_INDEX_MAX-1) {
                    av_log(mlz->context, AV_LOG_ERROR, "MLZ dic index error.\n");
                    return count;
                }
                if (( offset > (DIC_INDEX_MAX - 1))) {
                    av_log(mlz->context, AV_LOG_ERROR, "MLZ dic offset error.\n");
                    return count;
                }
            }
            break;
        }
    }
    return count;
}

static int input_code(GetBitContext* gb, int len) {
    int tmp_code = 0;
    int i;
    for (i = 0; i < len; ++i) {
        tmp_code |= get_bits1(gb) << i;
    }
    return tmp_code;
}

int ff_mlz_decompression(MLZ* mlz, GetBitContext* gb, int size, unsigned char *buff) {
    MLZDict *dict = mlz->dict;
    unsigned long output_chars;
    int string_code, last_string_code, char_code;

    string_code = 0;
    char_code   = -1;
    last_string_code = -1;
    output_chars = 0;

    while (output_chars < size) {
        string_code = input_code(gb, mlz->dic_code_bit);
        switch (string_code) {
            case FLUSH_CODE:
            case MAX_CODE:
                ff_mlz_flush_dict(mlz);
                char_code = -1;
                last_string_code = -1;
                break;
            case FREEZE_CODE:
                mlz->freeze_flag = 1;
                break;
            default:
                if (string_code > mlz->current_dic_index_max) {
                    av_log(mlz->context, AV_LOG_ERROR, "String code %d exceeds maximum value of %d.\n", string_code, mlz->current_dic_index_max);
                    return output_chars;
                }
                if (string_code == (int) mlz->bump_code) {
                    ++mlz->dic_code_bit;
                    mlz->current_dic_index_max *= 2;
                    mlz->bump_code = mlz->current_dic_index_max - 1;
                } else {
                    if (string_code >= mlz->next_code) {
                        int ret = decode_string(mlz, &buff[output_chars], last_string_code, &char_code, size - output_chars);
                        if (ret < 0 || ret > size - output_chars) {
                            av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
                            return output_chars;
                        }
                        output_chars += ret;
                        ret = decode_string(mlz, &buff[output_chars], char_code, &char_code, size - output_chars);
                        if (ret < 0 || ret > size - output_chars) {
                            av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
                            return output_chars;
                        }
                        output_chars += ret;
                        set_new_entry_dict(dict, mlz->next_code, last_string_code, char_code);
                        if (mlz->next_code >= TABLE_SIZE - 1) {
                            av_log(mlz->context, AV_LOG_ERROR, "Too many MLZ codes\n");
                            return output_chars;
                        }
                        mlz->next_code++;
                    } else {
                        int ret = decode_string(mlz, &buff[output_chars], string_code, &char_code, size - output_chars);
                        if (ret < 0 || ret > size - output_chars) {
                            av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
                            return output_chars;
                        }
                        output_chars += ret;
                        if (output_chars <= size && !mlz->freeze_flag) {
                            if (last_string_code != -1) {
                                set_new_entry_dict(dict, mlz->next_code, last_string_code, char_code);
                                if (mlz->next_code >= TABLE_SIZE - 1) {
                                    av_log(mlz->context, AV_LOG_ERROR, "Too many MLZ codes\n");
                                    return output_chars;
                                }
                                mlz->next_code++;
                            }
                        } else {
                            break;
                        }
                    }
                    last_string_code = string_code;
                }
                break;
        }
    }
    return output_chars;
}


Generated by: GCOVR (Version 4.1)

Line	Branch	Exec	Source
1			/*
2			* Copyright (c) 2016 Umair Khan <omerjerk@gmail.com>
3			*
4			* This file is part of FFmpeg.
5			*
6			* FFmpeg is free software; you can redistribute it and/or
7			* modify it under the terms of the GNU Lesser General Public
8			* License as published by the Free Software Foundation; either
9			* version 2.1 of the License, or (at your option) any later version.
10			*
11			* FFmpeg is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14			* Lesser General Public License for more details.
15			*
16			* You should have received a copy of the GNU Lesser General Public
17			* License along with FFmpeg; if not, write to the Free Software
18			* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19			*/
20
21			#include "mlz.h"
22
23			av_cold void ff_mlz_init_dict(void* context, MLZ *mlz) {
24			mlz->dict = av_mallocz_array(TABLE_SIZE, sizeof(*mlz->dict));
25
26			mlz->flush_code = FLUSH_CODE;
27			mlz->current_dic_index_max = DIC_INDEX_INIT;
28			mlz->dic_code_bit = CODE_BIT_INIT;
29			mlz->bump_code = (DIC_INDEX_INIT - 1);
30			mlz->next_code = FIRST_CODE;
31			mlz->freeze_flag = 0;
32			mlz->context = context;
33			}
34
35			av_cold void ff_mlz_flush_dict(MLZ *mlz) {
36			MLZDict *dict = mlz->dict;
37			int i;
38			for ( i = 0; i < TABLE_SIZE; i++ ) {
39			dict[i].string_code = CODE_UNSET;
40			dict[i].parent_code = CODE_UNSET;
41			dict[i].match_len = 0;
42			}
43			mlz->current_dic_index_max = DIC_INDEX_INIT;
44			mlz->dic_code_bit = CODE_BIT_INIT; // DicCodeBitInit;
45			mlz->bump_code = mlz->current_dic_index_max - 1;
46			mlz->next_code = FIRST_CODE;
47			mlz->freeze_flag = 0;
48			}
49
50			static void set_new_entry_dict(MLZDict* dict, int string_code, int parent_code, int char_code) {
51			dict[string_code].parent_code = parent_code;
52			dict[string_code].string_code = string_code;
53			dict[string_code].char_code = char_code;
54			if (parent_code < FIRST_CODE) {
55			dict[string_code].match_len = 2;
56			} else {
57			dict[string_code].match_len = (dict[parent_code].match_len) + 1;
58			}
59			}
60
61			static int decode_string(MLZ* mlz, unsigned char buff, int string_code, int first_char_code, unsigned long bufsize) {
62			MLZDict* dict = mlz->dict;
63			unsigned long count, offset;
64			int current_code, parent_code, tmp_code;
65
66			count = 0;
67			current_code = string_code;
68			*first_char_code = CODE_UNSET;
69
70			while (count < bufsize) {
71			switch (current_code) {
72			case CODE_UNSET:
73			return count;
74			break;
75			default:
76			if (current_code < FIRST_CODE) {
77			*first_char_code = current_code;
78			buff[0] = current_code;
79			count++;
80			return count;
81			} else {
82			offset = dict[current_code].match_len - 1;
83			tmp_code = dict[current_code].char_code;
84			if (offset >= bufsize) {
85			av_log(mlz->context, AV_LOG_ERROR, "MLZ offset error.\n");
86			return count;
87			}
88			buff[offset] = tmp_code;
89			count++;
90			}
91			current_code = dict[current_code].parent_code;
92			if ((current_code < 0) \|\| (current_code > (DIC_INDEX_MAX - 1))) {
93			av_log(mlz->context, AV_LOG_ERROR, "MLZ dic index error.\n");
94			return count;
95			}
96			if (current_code > FIRST_CODE) {
97			parent_code = dict[current_code].parent_code;
98			offset = (dict[current_code].match_len) - 1;
99			if (parent_code < 0 \|\| parent_code > DIC_INDEX_MAX-1) {
100			av_log(mlz->context, AV_LOG_ERROR, "MLZ dic index error.\n");
101			return count;
102			}
103			if (( offset > (DIC_INDEX_MAX - 1))) {
104			av_log(mlz->context, AV_LOG_ERROR, "MLZ dic offset error.\n");
105			return count;
106			}
107			}
108			break;
109			}
110			}
111			return count;
112			}
113
114			static int input_code(GetBitContext* gb, int len) {
115			int tmp_code = 0;
116			int i;
117			for (i = 0; i < len; ++i) {
118			tmp_code \|= get_bits1(gb) << i;
119			}
120			return tmp_code;
121			}
122
123			int ff_mlz_decompression(MLZ* mlz, GetBitContext* gb, int size, unsigned char *buff) {
124			MLZDict *dict = mlz->dict;
125			unsigned long output_chars;
126			int string_code, last_string_code, char_code;
127
128			string_code = 0;
129			char_code = -1;
130			last_string_code = -1;
131			output_chars = 0;
132
133			while (output_chars < size) {
134			string_code = input_code(gb, mlz->dic_code_bit);
135			switch (string_code) {
136			case FLUSH_CODE:
137			case MAX_CODE:
138			ff_mlz_flush_dict(mlz);
139			char_code = -1;
140			last_string_code = -1;
141			break;
142			case FREEZE_CODE:
143			mlz->freeze_flag = 1;
144			break;
145			default:
146			if (string_code > mlz->current_dic_index_max) {
147			av_log(mlz->context, AV_LOG_ERROR, "String code %d exceeds maximum value of %d.\n", string_code, mlz->current_dic_index_max);
148			return output_chars;
149			}
150			if (string_code == (int) mlz->bump_code) {
151			++mlz->dic_code_bit;
152			mlz->current_dic_index_max *= 2;
153			mlz->bump_code = mlz->current_dic_index_max - 1;
154			} else {
155			if (string_code >= mlz->next_code) {
156			int ret = decode_string(mlz, &buff[output_chars], last_string_code, &char_code, size - output_chars);
157			if (ret < 0 \|\| ret > size - output_chars) {
158			av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
159			return output_chars;
160			}
161			output_chars += ret;
162			ret = decode_string(mlz, &buff[output_chars], char_code, &char_code, size - output_chars);
163			if (ret < 0 \|\| ret > size - output_chars) {
164			av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
165			return output_chars;
166			}
167			output_chars += ret;
168			set_new_entry_dict(dict, mlz->next_code, last_string_code, char_code);
169			if (mlz->next_code >= TABLE_SIZE - 1) {
170			av_log(mlz->context, AV_LOG_ERROR, "Too many MLZ codes\n");
171			return output_chars;
172			}
173			mlz->next_code++;
174			} else {
175			int ret = decode_string(mlz, &buff[output_chars], string_code, &char_code, size - output_chars);
176			if (ret < 0 \|\| ret > size - output_chars) {
177			av_log(mlz->context, AV_LOG_ERROR, "output chars overflow\n");
178			return output_chars;
179			}
180			output_chars += ret;
181			if (output_chars <= size && !mlz->freeze_flag) {
182			if (last_string_code != -1) {
183			set_new_entry_dict(dict, mlz->next_code, last_string_code, char_code);
184			if (mlz->next_code >= TABLE_SIZE - 1) {
185			av_log(mlz->context, AV_LOG_ERROR, "Too many MLZ codes\n");
186			return output_chars;
187			}
188			mlz->next_code++;
189			}
190			} else {
191			break;
192			}
193			}
194			last_string_code = string_code;
195			}
196			break;
197			}
198			}
199			return output_chars;
200			}