From ec1b6e0cd404b2f7f4d202802b1c0a40d52fc9b0 Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Tue, 5 Mar 2024 21:16:01 +0100 Subject: [PATCH] avcodec/ccaption_dec: Avoid relocations for strings The longest string here takes four bytes, so using an array of pointers is wasteful even when ignoring the cost of relocations; the lack of relocations also implies that this array will now be put into .rodata and not into .data.rel.ro. Static asserts are used to ensure that all strings are always properly zero-terminated. Tested-by: Marth64 Signed-off-by: Andreas Rheinhardt --- libavcodec/ccaption_dec.c | 215 ++++++++++++++++++++------------------ 1 file changed, 115 insertions(+), 100 deletions(-) diff --git a/libavcodec/ccaption_dec.c b/libavcodec/ccaption_dec.c index 95143e7e46..1550e4b253 100644 --- a/libavcodec/ccaption_dec.c +++ b/libavcodec/ccaption_dec.c @@ -67,108 +67,123 @@ enum cc_charset { CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH, }; -static const char *charset_overrides[4][128] = +#define CHARSET_OVERRIDE_LIST(START_SET, ENTRY, END_SET) \ + START_SET(CCSET_BASIC_AMERICAN) \ + ENTRY(0x27, "\u2019") \ + ENTRY(0x2a, "\u00e1") \ + ENTRY(0x5c, "\u00e9") \ + ENTRY(0x5e, "\u00ed") \ + ENTRY(0x5f, "\u00f3") \ + ENTRY(0x60, "\u00fa") \ + ENTRY(0x7b, "\u00e7") \ + ENTRY(0x7c, "\u00f7") \ + ENTRY(0x7d, "\u00d1") \ + ENTRY(0x7e, "\u00f1") \ + ENTRY(0x7f, "\u2588") \ + END_SET \ + START_SET(CCSET_SPECIAL_AMERICAN) \ + ENTRY(0x30, "\u00ae") \ + ENTRY(0x31, "\u00b0") \ + ENTRY(0x32, "\u00bd") \ + ENTRY(0x33, "\u00bf") \ + ENTRY(0x34, "\u2122") \ + ENTRY(0x35, "\u00a2") \ + ENTRY(0x36, "\u00a3") \ + ENTRY(0x37, "\u266a") \ + ENTRY(0x38, "\u00e0") \ + ENTRY(0x39, "\u00A0") \ + ENTRY(0x3a, "\u00e8") \ + ENTRY(0x3b, "\u00e2") \ + ENTRY(0x3c, "\u00ea") \ + ENTRY(0x3d, "\u00ee") \ + ENTRY(0x3e, "\u00f4") \ + ENTRY(0x3f, "\u00fb") \ + END_SET \ + START_SET(CCSET_EXTENDED_SPANISH_FRENCH_MISC) \ + ENTRY(0x20, "\u00c1") \ + ENTRY(0x21, "\u00c9") \ + ENTRY(0x22, "\u00d3") \ + ENTRY(0x23, "\u00da") \ + ENTRY(0x24, "\u00dc") \ + ENTRY(0x25, "\u00fc") \ + ENTRY(0x26, "\u00b4") \ + ENTRY(0x27, "\u00a1") \ + ENTRY(0x28, "*") \ + ENTRY(0x29, "\u2018") \ + ENTRY(0x2a, "-") \ + ENTRY(0x2b, "\u00a9") \ + ENTRY(0x2c, "\u2120") \ + ENTRY(0x2d, "\u00b7") \ + ENTRY(0x2e, "\u201c") \ + ENTRY(0x2f, "\u201d") \ + ENTRY(0x30, "\u00c0") \ + ENTRY(0x31, "\u00c2") \ + ENTRY(0x32, "\u00c7") \ + ENTRY(0x33, "\u00c8") \ + ENTRY(0x34, "\u00ca") \ + ENTRY(0x35, "\u00cb") \ + ENTRY(0x36, "\u00eb") \ + ENTRY(0x37, "\u00ce") \ + ENTRY(0x38, "\u00cf") \ + ENTRY(0x39, "\u00ef") \ + ENTRY(0x3a, "\u00d4") \ + ENTRY(0x3b, "\u00d9") \ + ENTRY(0x3c, "\u00f9") \ + ENTRY(0x3d, "\u00db") \ + ENTRY(0x3e, "\u00ab") \ + ENTRY(0x3f, "\u00bb") \ + END_SET \ + START_SET(CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH) \ + ENTRY(0x20, "\u00c3") \ + ENTRY(0x21, "\u00e3") \ + ENTRY(0x22, "\u00cd") \ + ENTRY(0x23, "\u00cc") \ + ENTRY(0x24, "\u00ec") \ + ENTRY(0x25, "\u00d2") \ + ENTRY(0x26, "\u00f2") \ + ENTRY(0x27, "\u00d5") \ + ENTRY(0x28, "\u00f5") \ + ENTRY(0x29, "{") \ + ENTRY(0x2a, "}") \ + ENTRY(0x2b, "\\") \ + ENTRY(0x2c, "^") \ + ENTRY(0x2d, "_") \ + ENTRY(0x2e, "|") \ + ENTRY(0x2f, "~") \ + ENTRY(0x30, "\u00c4") \ + ENTRY(0x31, "\u00e4") \ + ENTRY(0x32, "\u00d6") \ + ENTRY(0x33, "\u00f6") \ + ENTRY(0x34, "\u00df") \ + ENTRY(0x35, "\u00a5") \ + ENTRY(0x36, "\u00a4") \ + ENTRY(0x37, "\u00a6") \ + ENTRY(0x38, "\u00c5") \ + ENTRY(0x39, "\u00e5") \ + ENTRY(0x3a, "\u00d8") \ + ENTRY(0x3b, "\u00f8") \ + ENTRY(0x3c, "\u250c") \ + ENTRY(0x3d, "\u2510") \ + ENTRY(0x3e, "\u2514") \ + ENTRY(0x3f, "\u2518") \ + END_SET \ + +static const char charset_overrides[4][128][sizeof("\u266a")] = { - [CCSET_BASIC_AMERICAN] = { - [0x27] = "\u2019", - [0x2a] = "\u00e1", - [0x5c] = "\u00e9", - [0x5e] = "\u00ed", - [0x5f] = "\u00f3", - [0x60] = "\u00fa", - [0x7b] = "\u00e7", - [0x7c] = "\u00f7", - [0x7d] = "\u00d1", - [0x7e] = "\u00f1", - [0x7f] = "\u2588" - }, - [CCSET_SPECIAL_AMERICAN] = { - [0x30] = "\u00ae", - [0x31] = "\u00b0", - [0x32] = "\u00bd", - [0x33] = "\u00bf", - [0x34] = "\u2122", - [0x35] = "\u00a2", - [0x36] = "\u00a3", - [0x37] = "\u266a", - [0x38] = "\u00e0", - [0x39] = "\u00A0", - [0x3a] = "\u00e8", - [0x3b] = "\u00e2", - [0x3c] = "\u00ea", - [0x3d] = "\u00ee", - [0x3e] = "\u00f4", - [0x3f] = "\u00fb", - }, - [CCSET_EXTENDED_SPANISH_FRENCH_MISC] = { - [0x20] = "\u00c1", - [0x21] = "\u00c9", - [0x22] = "\u00d3", - [0x23] = "\u00da", - [0x24] = "\u00dc", - [0x25] = "\u00fc", - [0x26] = "\u00b4", - [0x27] = "\u00a1", - [0x28] = "*", - [0x29] = "\u2018", - [0x2a] = "-", - [0x2b] = "\u00a9", - [0x2c] = "\u2120", - [0x2d] = "\u00b7", - [0x2e] = "\u201c", - [0x2f] = "\u201d", - [0x30] = "\u00c0", - [0x31] = "\u00c2", - [0x32] = "\u00c7", - [0x33] = "\u00c8", - [0x34] = "\u00ca", - [0x35] = "\u00cb", - [0x36] = "\u00eb", - [0x37] = "\u00ce", - [0x38] = "\u00cf", - [0x39] = "\u00ef", - [0x3a] = "\u00d4", - [0x3b] = "\u00d9", - [0x3c] = "\u00f9", - [0x3d] = "\u00db", - [0x3e] = "\u00ab", - [0x3f] = "\u00bb", - }, - [CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH] = { - [0x20] = "\u00c3", - [0x21] = "\u00e3", - [0x22] = "\u00cd", - [0x23] = "\u00cc", - [0x24] = "\u00ec", - [0x25] = "\u00d2", - [0x26] = "\u00f2", - [0x27] = "\u00d5", - [0x28] = "\u00f5", - [0x29] = "{", - [0x2a] = "}", - [0x2b] = "\\", - [0x2c] = "^", - [0x2d] = "_", - [0x2e] = "|", - [0x2f] = "~", - [0x30] = "\u00c4", - [0x31] = "\u00e4", - [0x32] = "\u00d6", - [0x33] = "\u00f6", - [0x34] = "\u00df", - [0x35] = "\u00a5", - [0x36] = "\u00a4", - [0x37] = "\u00a6", - [0x38] = "\u00c5", - [0x39] = "\u00e5", - [0x3a] = "\u00d8", - [0x3b] = "\u00f8", - [0x3c] = "\u250c", - [0x3d] = "\u2510", - [0x3e] = "\u2514", - [0x3f] = "\u2518", +#define START_SET(IDX) \ + [IDX] = { +#define ENTRY(idx, string) \ + [idx] = string, +#define END_SET \ }, + CHARSET_OVERRIDE_LIST(START_SET, ENTRY, END_SET) }; +#define EMPTY_START(IDX) +#define EMPTY_END +#define ASSERT_ENTRY(IDX, str) \ + _Static_assert(sizeof(str) <= sizeof(charset_overrides[0][0]), \ + "'" str "' string takes too much space"); +CHARSET_OVERRIDE_LIST(EMPTY_START, ASSERT_ENTRY, EMPTY_END) static const unsigned char bg_attribs[8] = // Color { @@ -571,7 +586,7 @@ static int capture_screen(CCaptionSubContext *ctx) prev_color = color[j]; prev_bg_color = bg[j]; override = charset_overrides[(int)charset[j]][(int)row[j]]; - if (override) { + if (override[0]) { av_bprintf(&ctx->buffer[bidx], "%s%s%s%s%s", e_tag, s_tag, c_tag, b_tag, override); seen_char = 1; } else if (row[j] == ' ' && !seen_char) {